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PubMed1987

Phase I trial of escalating doses of cisplatin in hypertonic saline.

A phase I trial of escalating doses of cisplatin (CDDP) in 3% sodium chloride was conducted to evaluate the toxicity of this method of administration. The maximally tolerated dose (MTD) was 40 mg/m2/d X 5 (200 mg/m2) in previously untreated patients, with dose-limiting leukopenia occurring on day 24 (median; range, 19 to 28). Nephrotoxicity was minimal. Ototoxicity was dose limiting in two patients. Peripheral neuropathy was observed in only one patient, but few patients received multiple courses of therapy. Six partial responses (PR) were observed in 47 patients, including two patients with refractory breast cancer and four with squamous cell carcinoma of head and neck origin. Two of the four patients with head and neck cancer had been previously treated with conventional doses of CDDP, suggesting a possible dose-response phenomenon in this disease. The saline infusion was well tolerated by older patients, suggesting that this method of administration can be safely used in those CDDP-sensitive malignancies that occur in older patients.

Adult↗
PubMed1996

Lack of cross-tolerance between haloperidol and clozapine towards Fos-protein induction in rat forebrain regions.

We investigated whether the acute effects of haloperidol and clozapine on Fos expression in the rat forebrain are mediated by the same receptors through evaluation of cross-tolerance, particularly in the commonly affected areas. Acutely administered haloperidol (1 mg/kg. i.p.) and clozapine (20 mg/kg, i.p.) induce regionally different (e.g., the striatum, the hypothalamic paraventricular and supraoptic nuclei, and the central amygdala) and overlapping (e.g., the nucleus accumbens and the lateral septum) patterns of Fos-protein distribution in the rat forebrain. After long-term treatment, part of the acute effects of these drugs disappears in most brain areas, except in the lateral septum, the hypothalamic paraventricular and supraoptic nuclei and the amygdala following haloperidol administration. Cross-tolerance between haloperidol and clozapine was determined by administering a challenge dose of the one antipsychotic, following a 21-day pretreatment with the same or the other drug or saline. In none of the investigated brain regions was cross-tolerance towards Fos-protein induction found after haloperidol challenge in the clozapine-treated rats. Conversely, a competitive dose of clozapine in long-term haloperidol-treated rats showed cross-tolerance in the lateral septum, while the common effect of the drugs in both the dorsomedial and the dorsolateral parts of the striatum was very small. These findings indicate that, for the major part, the responses to haloperidol and clozapine are mediated by different receptors, even in brain areas that are affected by both drugs.

Animals↗
PubMed1990

Systemic amiloride inhibits experimentally induced neovascularization.

Amiloride is an inhibitor of urokinase-type plasminogen activator, and might therefore have an inhibitory effect on neovascularization. Neovascularization was induced in rabbit corneas via local implantation of prostaglandin E1 pellets prepared in a slow-release polymer. Animals received daily intraperitoneal injections of 30 mg of amiloride, or an equivalent volume of saline solution for 5 days; both were well tolerated without severe untoward effect. Neovascular response, as documented by corneal photographs, was evaluated after 5 days of injections. The area of induced corneal neovascularization was decreased by 55% in animals receiving amiloride when compared with controls. Thus, amiloride and similar compounds may prove useful in the study and management of neovascularization.

Alprostadil↗
PubMed1984

Adaptation of plants to mineral stress in problem soils.

Crop production depends on interactions among genetic potentials of plants and various stress factors in the environment. Mineral stresses in the form of toxicity or deficiency are not always economically correctable with current technology. But plant species, and genotypes within species, differ widely in tolerance to different mineral stresses, and some of these differences are known to be genetically controlled. Hence, a viable alternative or supplemental approach is to adapt plants more precisely to soils. Soil fertility programmes of the past have emphasized 'changing the soil to fit the plant'. As a result, many crop cultivars have been developed under nearly ideal conditions of pH and soil fertility and hence cannot tolerate the stresses encountered in marginal soils. There is, therefore, a great need for stress-tolerant plant genotypes for use in a 'minimum input' system of agriculture for problem soils. The merits of tailoring the plant to fit the soil have only recently been recognized, even by the scientific community. However, within the last decade multidisciplinary teams of scientists have been formed in several countries, and considerable progress is being made in selecting and breeding plants for greater nutrient efficiency and for tolerance to such factors as aluminium toxicity and salinity. In view of problems in world food and energy production and distribution, this approach should receive the highest priority.

Adaptation, Biological↗
PubMed2004

Tropical ecotoxicity testing with Ceriodaphnia cornuta.

The Sai Gon-Dong Nai river system in southern Vietnam is of great social and economic importance yet receives a large amount of industrial, domestic, and agricultural discharges. Toxicity assessment has started to become an issue in Vietnam, and it is important to employ a test system that is appropriate for typical Vietnamese conditions with a species that is representative of the invertebrates living in its aquatic ecosystems. The aim of this study was to develop and to validate an ecotoxicity test with an autochthonous organism. The microcrustacean Ceriodaphnia cornuta (Cladocera) was isolated from the Sai Gon River. A protocol was developed for the culturing of the organisms, and satisfactory results were obtained for long-term reproduction of C. cornuta. Quality control criteria were established. The toxicity of two relevant pesticides (diazinon and methyl parathion) and two metals (chromium and mercury) to C. cornuta was evaluated and compared to the standard organisms for ecotoxicological testing: Daphnia magna and Vibrio fischeri. Nonlinear regression models were applied to estimate such parameters as EC(50). The results of acute toxicity tests showed that C. cornuta was less tolerant than D. magna and V. fischeri to salinity and that C. cornuta was more sensitive than D. magna and V. fischeri to potassium dichromate, diazinon, methyl parathion, and mercury.

Aliivibrio fischeri↗
PubMed1981

Activity of a non-hallucinogenic ergoline derivative, lisuride, in an animal behavior model for hallucinogens.

The behavioral effects of IP administration of lisuride, a non-hallucinogenic iso-lysergic acid amide analog structurally related to d-lysergic acid diethylamide (LSD), were examined in 15 cats. Ten animals were given saline or 6.25, 12.5, 25, 50, or 100 micrograms/kg of lisuride and observed for 1 h by a rater blind to dose. There was a statistically significant effect of lisuride dose on the frequency of occurrence of the behaviors limb flicking, grooming, and abortive grooming. A time-course study with five cats at the most effective lisuride dose, 50 micrograms/kg, revealed that the frequencies of occurrence of these behaviors reached a maximum during the first 2 h post dose, and were comparable to frequencies after saline by 6 h post dose. An acute tolerance study with four cats scored for 90 min post dose revealed no significant tolerance to a 50 micrograms/kg lisuride test dose administered 6, 24, or 72 h after an initial 50 micrograms/kg dose. Acute cross tolerance studies with four cats scored for 90 min after an initial dose of 50 micrograms/kg of LSD or of lisuride, followed 24 h later by 50 micrograms/kg of lisuride or LSD, revealed no significant cross tolerance. The potency of lisuride relative to LSD was evaluated in six cats that were scored for 60 min following 25 and 50 micrograms/kg of LSD and of lisuride. On a molar basis, scores after lisuride were 51% and 67% those after LSD for limb flicking and grooming. These results indicate that lisuride, a non-hallucinogenic iso-lysergic acid derivative, is a false positive in the animal behavior model for hallucinogens.

Animals↗
PubMed2004

DNA-repair potential of Halomonas spp. from the Salt Plains Microbial Observatory of Oklahoma.

The Great Salt Plains (GSP), an unvegetated, barren salt flat that is part of the Salt Plains National Wildlife Refuge near Cherokee, Oklahoma, is the site of the Salt Plains Microbial Observatory. At the GSP the briny remains of an ancient sea rise to the surface, evaporate under dry conditions, and leave crusts of white salt. Adaptation to this environment requires development of coping mechanisms providing tolerance to desiccating conditions due to the high salinity, extreme temperatures, alkaline pH, unrelenting exposure to solar UV radiation, and prevailing winds. Several lines of evidence suggest that the same DNA repair mechanisms that are usually associated with UV light or chemically induced DNA damage are also important in protecting microbes from desiccation. Because little is known about the DNA repair capacity of microorganisms from hypersaline terrestrial environments, we explored the DNA repair capacity of microbial isolates from the GSP. We used survival following exposure to UV light as a convenient tool to assess DNA repair capacity. Two species of Halomonas (H. salina and H. venusta) that have been isolated repeatedly from the GSP were chosen for analysis. The survival profiles were compared to those of Escherichia coli, Pseudomonas aeruginosa, and Halomonas spp. from aquatic saline environments. Survival of GSP organisms exceeded that of the freshwater organism P. aeruginosa, although they survived no better than E. coli. The GSP isolates were much more resistance to killing by UV than were the aquatic species of Halomonas reported in the literature [Martin et al. (2000) Can J Microbiol 46:180-187]. Unlike E. coli, the GSP isolates did not appear to have an inducible, error-prone repair mechanism. However, they demonstrated high levels of spontaneous mutation.

Adaptation, Physiological↗
PubMed2026

Comparative metagenomic analysis of microbial communities: unravelling microbial communities from the great Rann of Kachchh and coastal saltpans, Gujarat, India.

Hypersaline environments exhibit extreme physiochemical conditions yet support diverse microbial communities. These communities are not only ecologically important but also possess substantial potential for biotechnological exploitation. In this study, we employed a comparative metagenomic approach to assess microbial diversity using two distinct methodologies: (1) direct DNA extraction from raw sediment, and (2) DNA extraction following halophilic enrichment in selective media. Sediment samples were collected from multiple sites and pooled together within the Rann of Kachchh and close-by saltpans and were analysed using 16S rRNA sequencing coupled with bioinformatics pipelines. The results revealed pronounced differences in microbial community composition between the two approaches. Raw sediment samples exhibited significantly higher alpha diversity, with dominant taxa including Halobacterota, Cyanobacteria, and Desulfobacterota, with a substantial proportion of unclassified genera. In contrast, enriched samples were dominated by fast-growing, culturable genera such as Halobacterium, Alkalibacillus, and Candidatus haloredivivus. Principal Coordinate Analysis (PCoA) of beta diversity demonstrated distinct clustering between raw and enriched communities, even within samples from the same sites, underscoring the selective bias introduced by enrichment procedures. These findings emphasise that the methodological choice strongly influences the observed microbial diversity. The aim of this study was to compare microbial community composition in raw hypersaline sediments and enrichment cultures using metagenomic sequencing, to evaluate how enrichment selectively favours specific halophilic taxa. This comparative approach allows identification of the microbial groups that rapidly proliferate under controlled hypersaline conditions, thereby complementing direct environmental sequencing. By integrating both direct and enrichment-based metagenomic approaches, a more comprehensive understanding of microbial community structure in hypersaline environments can be achieved.

India↗
PubMed1992

Inhibition of dopamine uptake by cocaine and nicotine: tolerance to chronic treatments.

Chronic administration of cocaine (50 mg/kg/day for 7 days, s.c. via an osmotic minipump) produced tolerance to inhibition of [3H]dopamine uptake by cocaine in rat striatum but did not produce cross-tolerance to inhibition of [3H]dopamine uptake by nicotine. Chronic nicotinic treatment (6 mg/kg/day for 7 days, s.c. via an osmotic minipump), however, produced tolerance to the inhibition of [3H]dopamine uptake by nicotine and cross-tolerance to inhibition of uptake by cocaine in rat striatum. Nicotine did not inhibit uptake of [3H]dopamine in the nucleus accumbens of saline-treated animals. In this tissue, both cocaine and nicotine treatments produced tolerance to cocaine, as in striatum. Unlike the effects on [3H]dopamine uptake, chronic cocaine infusion did not have any effect on the ability of cocaine to inhibit [3H]serotonin uptake in either brain region.

Animals↗
PubMed1993

Dopamine release and metabolism in nucleus accumbens and striatum of morphine-tolerant and nontolerant rats.

Morphine administered at high doses produces a biphasic locomotor effect, characterized by an initial locomotor depression, followed a short time later by hyperlocomotion. Prior exposure to morphine produces tolerance to the motor-depressive effects and sensitization to the motor-activating effects of morphine. Little is known of the neurochemical changes that occur to produce tolerance and sensitization to morphine. In the present study, we developed a morphine pretreatment regimen in rats that produced both tolerance and sensitization to a high (30 mg/kg) dose of morphine. Using in vivo microdialysis, we then measured dopamine (DA), dihydroxyphenylacetic acid (DOPAC), and homovanillic acid (HVA) release in the nucleus accumbens (NAC) and striatum (STR) in morphine- and saline-pretreated rats after acute morphine administration. In morphine-tolerant/sensitized rats, basal DA concentrations in the NAC were higher and levels of DOPAC and HVA in the NAC after acute morphine injection were greater compared to controls. These results suggest that the NAC, but not the STR, may be important in mediating tolerance and sensitization to opiates.

3,4-Dihydroxyphenylacetic Acid↗
PubMed1995

The effects of nicotine and nicotine withdrawal on taste reactivity.

The effect of nicotine pretreatment on the palatability of flavored solutions was assessed using the taste reactivity test. In Experiment 1, low doses of nicotine [0.2-0.4 mg/kg, subcutaneously (s.c.)] suppressed the aversive taste properties of quinine and quinine-sucrose mixture and enhanced the hedonic taste properties of sucrose (0.4 mg/kg, s.c.) in rats that were nicotine naive. In Experiment 2, rats were chronically preexposed to nicotine or saline over a period of 21 pretreatment days. Tolerance developed to the ability of nicotine to enhance the palatability of sucrose. Furthermore, rats that were chronically preexposed to nicotine displayed enhanced hedonic evaluation of sucrose 24 h after nicotine was withdrawn. These results confirm human self-reports that withdrawal from nicotine dependency enhances the palatability of sweet-tasting foods.

Animals↗
PubMed2006

Chronic tumor necrosis factor-alpha infusion in gravid C57BL6/J mice accelerates adipose tissue development in female offspring.

OBJECTIVE: Tumor necrosis factor (TNF)-alpha is thought to mediate, in part, the link between obesity and insulin resistance, and women with gestational diabetes mellitus (GDM) have raised serum TNF-alpha concentrations. Our objective was to investigate whether systemic TNF-alpha administration into gravid C57BL6/J mice causes a GDM-like syndrome and affects growth and adipose tissue (AT) development in the offspring. METHODS: We assessed glucose tolerance and reproductive outcome in mice infused with saline, or 2 mug or 4 mug recombinant mouse (rm)TNF-alpha by subcutaneous mini-osmotic pumps between days (d)11.5 and 18.5 of gestation. Subsequently, we studied the effects of the 2-mug dose on maternal AT metabolism. Finally, the growth of offspring exposed to 2 mug rmTNF-alpha in utero was followed until 8 weeks postnatal age. At 8 weeks, we assessed AT accumulation, as well as adipocyte area in white AT and insulin sensitivity in males, and adipokine mRNA levels in various AT depots in females. RESULTS: The peak glucose response to an intraperitoneal glucose stimulus in late-gravid mice and fetal weight were higher with 2 mug but not 4 mug rmTNF-alpha compared with saline; however, 2 mug TNF-alpha did not affect AT parameters. The female but not male offspring of these mice showed accelerated growth, hyperadiposity, robustly increased leptin expression in all AT depots, and raised fasting blood glucose. CONCLUSIONS: TNF-alpha infusion (2 mug for 7 days) in gravid mice resulted in a mild GDM syndrome and accelerated AT development in the offspring in a sex-specific manner. The data suggest that TNF-alpha mediates in part the effects of GDM on fetal growth and postnatal adiposity, and constitutes a potential mediator of intrauterine programming.

Adipose Tissue↗
PubMed1997

A comparison between microwave irradiation and decapitation: basal levels of dynorphin and enkephalin and the effect of chronic morphine treatment on dynorphin peptides.

Opioid peptides were analysed in tissue extracts of various brain structures and the pituitary gland from rats sacrificed by microwave irradiation, and compared with peptide levels in tissue extracts from decapitated rats. Dynorphin A, dynorphin B and Leu-enkephalinArg6, derived from prodynorphin, and Met-enkephalinArg6Phe7 from proenkephalin, were measured. Basal immunoreactive levels of dynorphin A and B were consistently higher in extracts from microwave-irradiated rats, whereas in these extracts immunoreactive levels of Leu-enkephalinArg6, an endogenous metabolite of dynorphin peptides, were either lower than, the same as or higher than in decapitated rats. Immunoreactive levels of Met-enkephalinArg6Phe7 were higher in microwave-irradiated rats. Effects of morphine treatment on prodynorphin peptide levels were evaluated and compared with previous findings in decapitated rats. Dynorphin immunoreactive levels were higher in the nucleus accumbens and striatum of morphine-tolerant rats than in corresponding areas in saline-treated rats. These results indicate tissue-specific metabolism of prodynorphin peptides and show that metabolism of opioid peptides occurs during the dissection procedure after decapitation of the rat even though precautions are taken to minimize degradation.

Animals↗
PubMed1997

Temporal dynamics of glutamate efflux in the prefrontal cortex and in the hippocampus following repeated stress: effects of pretreatment with saline or diazepam.

Acute stress has been associated with activation of glutamate efflux in forebrain structures. The present study sought to characterize the extracellular dynamics of glutamate in response to acute and repeated stress in the prefrontal cortex and hippocampus in rats. One-minute sampling of extracellular glutamate levels was performed during repeated tail-pinch stress. Animals were stressed three times, beginning at approximately 10.30 a.m. and continuing at 2.5-h intervals. In the prefrontal cortex, the initial 10-min tail pinch produced a robust increase in extracellular levels of glutamate. This increase was apparent immediately (i.e. 1 min) after the start of the stress procedure. The second tail pinch produced a smaller increase in glutamate levels while the third tail pinch did not significantly increase these levels. In the hippocampus, the initial stress response was smaller in magnitude than that observed in the prefrontal cortex. Furthermore, responses to subsequent tail pinches were similar to that seen following the first tail pinch. Treatment with diazepam (3 mg/kg/i.p.) 30 min before the first stress session abolished the stress response in the prefrontal cortex and hippocampus. However, in the prefrontal cortex, the second tail pinch (performed approximately 3 h after diazepam administration) produced a robust increase in glutamate efflux. In contrast, in the hippocampus of diazepam-treated rats, the second tail pinch produced a small delayed response. Pretreatment with saline resulted in non-significant responses to all three tail pinches in the prefrontal cortex. The present study suggests that: (i) stress produces a rapid increase in glutamate efflux in the prefrontal cortex and hippocampus, (ii) repeated stress reveals tolerance in the glutamatergic response in the prefrontal cortex, (iii) saline and diazepam pretreatment reduce the stress-induced efflux of glutamate in the prefrontal cortex, and (iv) exposure to diazepam may prevent the prefrontal cortex from adapting its response to the subsequent stressor. These finding are consistent with the role of the prefrontal cortex as a region which may regulate reactions to aversive stimuli.

Animals↗
PubMed2001

Diversity of pseudomonads isolated from three different plant rhizospheres.

AIMS: To study the diversity of the Pseudomonas populations isolated from three different plant rhizospheres, namely pearl millet, cotton and paddy, grown in saline soils along the coastline of Southern India. METHODS AND RESULTS: The Pseudomonas populations were analysed for their biochemical characters and genetic diversity using molecular tools including RAPD and PCR-RFLP. The biochemical characterization, antibiotic resistance assay and RAPD profiles revealed a largely homogeneous population. Even in PCR-RFLP restriction studies, only two groups of isolates were seen. One group was predominant in all three rhizospheres, while the other minor group consisted of salt-sensitive isolates restricted to the paddy rhizosphere alone. CONCLUSIONS: It was observed that increasing salinity caused a predominant selection of salt-tolerant species, in particular Ps. pseudoalcaligenes and Ps. alcaligenes, irrespective of the host rhizosphere. SIGNIFICANCE AND IMPACT OF THE STUDY: This study has reinstated the importance of the soil over the host plant with regard to rhizosphere populations. It has also resulted in the isolation of several salt-tolerant Pseudomonas strains, which are being screened for their biological control activity against common plant pathogens of the coastal agri-ecosystem.

DNA, Ribosomal↗
PubMed2005

Intra-vaginal hydrosonography and cervical length assessment in pregnant women before induction of labour: a modified technique.

The objective of this study was to demonstrate a new simple technique in introducing saline into the vagina during trans-vaginal scan. This technique will help to identify the cervical length properly when it is difficult to delineate the cervix. This is a prospective study, which included 104 pregnant women who booked to have induction of labour at term over a period of 3 years. Women who were included in the study underwent a transvaginal scan to measure cervical length. Sterile saline was introduced into the vagina using either an ordinary syringe or an Endosampler and the cervical length re-measured. When the outer border of the cervix was not clearly visualised, there was a highly statistically significant difference (p < 0.001) between the medians of pre-and post-saline cervical length measurements. In contrast, no significant difference between the medians (p > 0.05) was detected when the outer border of the cervix was clearly delineated. In those women, who had previous surgery to the cervix, it was very difficult to identify the cervix at all without the saline injection during transvaginal scanning. We conclude that intra-vaginal saline can be used as a contrast medium to help delineate the cervix if it is difficult to identify during transvaginal scan. The Endosampler makes the introduction of the saline into the vagina easy, controlled and well tolerated.

Adolescent↗
PubMed2002

A randomized, controlled pilot study of the safety and efficacy of 4% icodextrin solution in the reduction of adhesions following laparoscopic gynaecological surgery.

BACKGROUND: Adhesion-related readmissions are frequent sequelae to gynaecological surgery. Attempts to prevent adhesions by separating healing peritoneal surfaces include site-specific barriers and hydroflotation by instilled solutions. Rapid absorption limits the effectiveness of solutions such as Ringer's lactated saline (RLS). This pilot study assessed the safety, tolerability and preliminary effectiveness of a non-viscous, iso-osmolar solution of 4% icodextrin, an alpha-1,4 glucose polymer with prolonged intraperitoneal residence, in reducing adhesions after laparoscopic gynaecological surgery. METHODS: Women aged > or = 18 years, requiring laparoscopic adnexal surgery (n = 62), were entered into a randomized, open-label, assessor-blinded, multicentre study to compare 4% icodextrin with RLS. Treatments were coded in blocks of four with equal randomization to each group, and pre-allocated to consecutively numbered patients. At least 100 ml per 30 min was used for intra-operative lavage, with 1 l instilled post-operatively. Per protocol analysis included all eligible patients (n = 53); reformation analysis required one or more baseline adhesion (n = 42). Incidence, extent and severity of post-operative adhesions were assessed at second-look laparoscopy after 6-12 weeks. Procedures were video-taped for third party, blinded assessment. RESULTS: Safety and tolerability (laboratory variables, adverse events, clinical follow-up) were good with no difference between treatments. A shift analysis of incidence-ranked adhesions (n = 53) showed apparent improvements in more patients with icodextrin than RLS (37 versus 15%; not significant). Adhesion score reduction (n = 42) was more frequent in icodextrin- than RLS-treated patients: incidence (52 versus 32%), extent (52 versus 47%), and severity (65 versus 37%). Despite greater baseline adhesions, median reformation was less after icodextrin (24%) than RLS (60%). The pilot study group sizes were not powered for statistical significance. CONCLUSIONS: In this preliminary study, 4% icodextrin lavage plus instillation was well tolerated and reduced adhesion formation and reformation following laparoscopic gynaecological surgery. A Phase III pivotal study is currently in progress.

Adult↗
PubMed1997

Regulation of levels of proline as an osmolyte in plants under water stress.

Compatible osmolytes are potent osmoprotectants that play a role in counteracting the effects of osmotic stress. Proline (Pro) is one of the most common compatible osmolytes in water-stressed plants. The accumulation of Pro in dehydrated plants is caused both by activation of the biosynthesis of Pro and by inactivation of the degradation of Pro. In plants, L-Pro is synthesized from L-glutamic acid (L-Glu) via delta(1)-pyrroline-5-carboxylate (P5C) by two enzymes, P5C synthetase (P5CS) and P5C reductase (P5CR). L-Pro is metabolized to L-Glu via P5C by two enzymes, proline dehydrogenase (oxidase) (ProDH; EC 1.5.99.8) and P5C dehydrogenase (P5CDH; EC 1.5.1.12). Such metabolism of Pro is inhibited when Pro accumulates during dehydration and it is activated when rehydration occurs. Under dehydration conditions, when expression of the gene for P5CS is strongly induced, expression of the gene for ProDH is inhibited. By contrast, under rehydration conditions, when the expression of the gene for ProDH is strongly induced, the expression of the gene for P5CS is inhibited. Thus, P5CS, which acts during the biosynthesis of Pro, and ProDH, which acts during the metabolism of Pro, appear to be the rate-limiting factors under water stress. Therefore, it is suggested that levels of Pro are regulated at the level of transcriptional the genes of these two enzymes during dehydration and rehydration. Moreover, it has been demonstrated that Pro acts as an osmoprotectant and that overproduction of Pro results in increased tolerance to osmotic stress of transgenic tobacco plants. Genetically engineered crop plants that overproduce Pro might, thus, acquire osmotolerance, namely, the ability to tolerate environmental stresses such as drought and high salinity.

1-Pyrroline-5-Carboxylate Dehydrogenase↗