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PubMed1982

Abolition by cycloheximide of caffeine-enhanced lethality of alkylating agents in hamster cells.

Greatly enhanced lethality for Syrian hamster cells (baby hamster kidney cells and polyomavirus-transformed derivative of baby hamster kidney cells) that had been treated with alkylating agents or ultraviolet light is produced by caffeine. Thus, nitrogen mustard [methylbis(beta-chloroethyl)amine] (HN2) at 0.5 microM decreased cell viability by only a few percent in the absence of caffeine. The addition of 2 mM caffeine during the first 24 hr after nitrogen mustard decreased viability more than 95%. Further kinetic studies of the caffeine effects using other alkylating agents indicate the existence of two modes which damaged cells become caffeine sensitive. Treatment with ultraviolet light or nitrogen mustard makes cells immediately sensitive to caffeine; cells treated with methyl methanesulfonate or N-methyl-N'-nitro-N-nitrosoguanidine, on the other hand, express their maximal caffeine sensitivity only about 15 to 20 hr later. A low concentration of cycloheximide completely abolished this caffeine effect. When 0.36 microM cycloheximide was present, loss of viability was negligible even in the presence of caffeine. Based on further experiments involving the timing of caffeine and cycloheximide additions, caffeine does not affect viability by itself but is involved with some substance such as a protein the rapid synthesis of which is prevented by cycloheximide. This substance does not appear to be needed for recovery from damage, but rather for the action of caffeine in fixing the damaging caused by alkylating agents.

Alkylating Agents↗
PubMed1980

[Biochemical and ultrastructural study of actidione-cycloheximide effect on fat intestinal absorption in the rat (author's transl)].

The biochemical and ultrastructural aspects of intestinall fat absorption and chylomicron formation have been studied in rats treated with actidione-cycloheximide. Rats were prepared with a catheter in the main mesenteric lymph duct. The next day, primor rapeseed oil containing 14C triolein was infused in the duodenum of control rats and actidione-cycloheximide treated rats four hours before experiments. In each case, the quantity of lipids absorbed was determined after six hours, and the lipids present in the mucosa were studied as were those present in the lymph collected throughout the absorption period. Furthermore, the ultrastructural study of the mucosa and the morphological study of the lymph lipoprotein particles were carried out using electron microscopy. Disappearance of intraluminal lipids and mucosal lipids appeared slightly impaired after actidione-cycloheximide treatment, but only a very small proportion of the infused lipids were recovered in the intestinal lymph (0.05% compared to 3% in control rats, Table I). The amount of esterified lipids found in the mucosa, after six hours, was clearly lower (49%) when compared with those of control rats (79%) (Table II). This suggests that, following inhibition of protein synthesis by actidione-cycloheximide, lymph fat absorption was much impaired. An alteration in cellular structure appeared in microscopic observations of treated rat enterocytes (Fig. 2 and 3) compared with the control (Fig. 1). Many whorl formations and autophagic vacuoles were included in these cytotoxic effects during lipid absorption. Treated animal enterocyte lipid particles did not have the organized structure of those in the controls. While lymph particles of control rats revealed a regular progression in size (Fig. 4A, B), lymph particles of treated-rats showed a few large chylomicrons (equal or far larger than in the controls) among small particles (Fig. 4 C, D, E); furthermore, evidence of coalescence might be observed (Fig. 4 F). All these observations emphasize the prevailing role of the different protein structures of the enterocytes during lipid intestinal absorption, particularly for chylomicron organization after long-chain fatty acid uptake.

Animals↗
PubMed1994

Glucose deprivation and acute cycloheximide treatment stimulate system L amino acid transport in cultured vascular smooth muscle cells.

The effect of glucose deprivation on the uptake of leucine has been examined in cultured vascular smooth muscle cells isolated from rat aortae. Equimolar substitution of sucrose or fructose for glucose in the culture medium enhanced the uptake of leucine in a time- and concentration-dependent manner. The effect was first detectable after 12 h and reached the maximum, 2-fold, after 48 h with an apparent half-maximal effect at 1 mM glucose and could be reversed after 48 h of glucose refeeding. The enhanced leucine uptake was completely inhibited by 2-amino-2-norbornane-carboxylic acid, a specific substrate for System L, but not by alpha-(methylamino)isobutyric acid or lysine. Kinetic analyses indicated that this stimulation was mediated via a homogenous system with a 1.7-fold increase in the Vmax without any change in the Km (0.15 mM). Prolonged treatments with cycloheximide (10 micrograms/ml) or actinomycin D (10 micrograms/ml) blocked this glucose deprivation effect and its reversal. However, cycloheximide also very rapidly stimulated leucine uptake, reaching the maximum, 2.5-fold over the basal at 1 h. This effect occurred at concentrations that matched its inhibition on protein synthesis (half-maximal at 0.1 micrograms/ml) and could be reproduced with puromycin as well as actinomycin D. The stimulatory effect of cycloheximide was also accompanied by an increase in the Vmax but not in the Km, being sensitive to 2-amino-2-norbornane-carboxylic acid inhibition only, and appeared to occur in an additive manner to that of glucose deprivation. Although the uptake of leucine was stimulated by glucose deprivation and brief exposure to cycloheximide, these treatments had no effect on the efflux of the substrate. These results are all consistent with the System L amino acids transport activity in cultured rat vascular smooth muscle cells being under the control of at least two non-hormonal regulatory mechanisms, one that is likely to involve a labile repressor molecule and the other involving de novo protein synthesis as a result of chronic glucose deprivation.

Animals↗
PubMed1977

[Effect of cycloheximide on the disintegration of the germinal vesicle membrane and on changes in the cortical layer in oocytes of the clawed toad and the starred sturgeon during maturation on exposure to active cytoplasm].

There was studied the effect of cycloheximide on the changes in the X. laevis and A. stellatus oocytes maturing under the influence of active cytoplasm, taken from the maturing oocytes, and, in the control series, under the influence of progesterone. The suppression of protein synthesis in the X. laevis oocytes by means of cycloheximide by 90--95% did not prevent the amplification of the factor of disintegration of the germinal vesicle membrane after 4 and 5 transfers of the active cytoplasm through the cycloheximide-treated oocytes; no pseudogastrulation was observed in such oocytes. Under the similar suppression of protein synthesis in the A. stellatus oocytes, the germinal vesicle did not break down already after the first injection of active cytoplasm; such oocytes acquried, however, the ability of cortical reaction. The cycloheximide-treated oocytes of both the species did not mature under the effect of progesterone. The fully grown A. stellatus oocytes matured after the injection of active cytoplasm from the mature X. laevis oocytes.

Animals↗
PubMed1998

Saprophytic and cycloheximide resistant fungi isolated from golden hamster.

Healthy hair samples from golden hamsters were examined for the presence of dermatophytes and non-dermatophytes using baiting technique and direct inoculation. Thirty-four species and 2 varieties attributed to 17 genera were recovered. Paecilomyces variotii (isolated from 84.4% of the examined hair) and Aspergillus niger (81.3%) were the more frequent isolates on Sabouraud's dextrose agar (SDA) without cycloheximide. Our results have clearly demonstrated that the hair of hamster was free from true dermatophytes. Using the dilution plate method many fungal species were isolated from cage material (7 genera and 10 species + 1 variety); from faeces (10 genera and 17 species); from standard chow (3 genera and 6 species) of hamster. P. variotii which was the most frequent fungus in the preceding 3 substrates was completely absent in the presence of cycloheximide in SDA. The present study has demonstrated for the first time the isolation of Trichophyton rubrum from hamster faeces. Also, several saprophytic and cycloheximide resistant fungi were isolated. In the air of hamster cage Cladosporium cladosporioides, Penicillium chrysogenum, Alternaria alternata and Scopulariopsis brevicaulis were the most dominant species on SDA with or without cycloheximide. Using the agar diffusion method, Aloe sap, onion oil, garlic bulb extract and aqueous leaf extracts of Andropogon citratus, Euphorbia sp. and Ruta graveolens were tested for their antifungal activity on 10 fungal species. It was observed that onion oil exhibited a high inhibitory effect against most of the tested fungi.

Animal Feed↗
PubMed2002

Cellular autophagic capacity changes during azaserine-induced tumour progression in the rat pancreas. Up-regulation in all premalignant stages and down-regulation with loss of cycloheximide sensitivity of segregation along with malignant transformation.

The knowledge of alterations in regulation of autophagy during tumorigenesis may also help our understanding of its normal control. We established an experimental system and reported recently that autophagic capacity, measured as the cell's capability of increasing segregation (formation of autophagosomes) and subsequent degradation of cytoplasmic quanta were highly increased in premalignant nodule cells 6 months after initiation by azaserine in the rat pancreas in vivo. In the present study, we followed changes of these autophagic functions throughout the tumour progression. We carried out electron-microscopic morphometrical analysis of the expansion of autophagic vacuole compartment and subcompartments induced by vinblastine (an in vivo segregation enhancer), as well as their regression upon segregation-inhibitor cycloheximide post-treatment. Premalignant tumour samples were taken at month 5, month 8 (nodules), month 10 and month 15 (adenomas) after initiation. In all these stages, a highly increased and varying autophagic capacity was found compared with the host tissue. The basal (non-stimulated) autophagic compartment was measurable only at month 5 and month 15, and its regression upon cycloheximide was consistent with increased basal autophagic activity. Compared with the host tissue, autophagic capacity profoundly decreased in the differentiated and anaplastic adenocarcinomas at month 20, when, surprisingly, cycloheximide was unable to inhibit segregation. Our conclusion is that down-regulation of the cycloheximide sensitive segregation and a partly compensatory up-regulation of an alternative pathway of segregation might occur along with malignant transformation.

Adenocarcinoma↗
PubMed1994

Synergistic effect of ethanol and cycloheximide on activation of freshly matured bovine oocytes.

Bovine follicular oocytes were collected from ovarian antral follicles (2 to 7 mm in diameter) from slaughtered cattle. They were matured in vitro (IVM) for 23 to 24 h and then activated. In Experiment 1, 4 concentrations of ethanol were compared. The activation rates of oocytes were 4, 12, 36 and 27%, respectively, following exposure for 7 min to 0, 5, 7 and 10% ethanol. In Experiment 2, 7% ethanol was tested with exposure times of 0, 5, 7.5 and 10 min, and 6, 32, 27 and 33% of the oocytes were activated, respectively. In Experiment 3 the synergistic effect of ethanol and electric pulse was compared within 4 treatments: A) 7% ethanol alone, B) electric pulse alone, C) ethanol first and then electric pulse treatment, and D) electric pulse first followed by ethanol exposure. Of the oocytes activated, 37, 31, 28 and 51%, respectively, were from Treatments A through D. In Experiments 4 and 5 the possible synergistic effect of ethanol and a protein synthesis inhibitor, cycloheximide, was studied within 4 treatments: A) parthenogenetic control with no activation treatment, B) ethanol alone, C) cycloheximide alone, and D) ethanol treatment followed by cycloheximide. The oocyte activation rates in Experiment 4 in Treatments A through D, respectively, were 9, 44, 43 and 84%. Corresponding values for development of oocytes to the 2 to 8-cell stage after culture for 3 d (Experiment 5) were 9, 20, 14 and 45%, respectively (P<0.05). In conclusion, exposure to 7% ethanol for 5 min followed by incubation with cycloheximide was the best activation treatment for bovine IVM oocytes.

Journal Article↗
PubMed1995

Time-dependent effects of cycloheximide and alpha-amanitin on meiotic resumption and progression in bovine follicular oocytes.

To identify the stage during maturation at which new protein and RNA are synthesized for meiotic resumption, follicular oocytes were cultured in TCM-199 with the protein synthesis inhibitor cycloheximide or the hnRNA synthesis inhibitor alpha-amanitin. Although the meiotic resumption of cumulus-enclosed oocytes was completely blocked by the addition of 25 microg/ml cycloheximide at 4 h after the onset of culture, 23% of oocytes cultured from 5 h post cultivation in the medium with cycloheximide underwent germinal vesicle breakdown (GVBD). By further delaying the addition of cycloheximide, the proportion of oocytes which underwent GVBD increased. Addition of the inhibitor at 8 h or more post cultivation resulted in GVBD occurring in more than 87% of oocytes, though none of them were able to proceed beyond the metaphase I stage. In contrast, the addition of 50 microg/ml alpha-amanitin from the onset of culture significantly reduced the proportion of GVBD to 75% in cumulus-enclosed oocytes, while no significant reduction in the proportions of GVBD was noted in the case of its addition from 1 h of culture onward. However, denuded oocytes were almost insensitive to any treatments with alpha-amanitin. These results indicate that protein synthesis in the oocytes and RNA synthesis in the cumulus cells soon after the onset of culture are necessary for GVBD and that continuous protein synthesis following GVBD is indispensable for progression of the meiotic division in bovine oocytes.

Journal Article↗
PubMed1966

Effect of cycloheximide on protein biosynthesis in rat liver.

1. The liver ribosomes of rats given cycloheximide by intraperitoneal injection incorporate less amino acid into protein than ribosomes from control rat liver when they are incubated in vitro with excess of Sephadex-treated cell sap. The effect is rapid, marked and persistent. 2. Cell sap from liver of cycloheximide-treated animals is inhibitory but the inhibition can be relieved almost entirely by treating the cell sap with Sephadex. No damage has been done to the cell-sap factors: it is suggested that the dissolved cycloheximide in the cell sap causes the inhibition. 3. Cycloheximide added in vitro inhibits amino acid incorporation into protein in the presence or absence of polyuridylic acid. The inhibition is lessened by addition of excess of cell sap but is not abolished. 4. The differences between these results and those obtained with mouse liver (Trakatellis, Montjar & Axelrod, 1965) might arise because of species differences in sensitivity to the drug.

Journal Article↗
PubMed1975

Mechanism of sulfate transport inhibition by cycloheximide in plant tissues.

Inhibition by cycloheximide of sulfate transport in both barley roots (Hordeum vulgare L.) and potato tuber (Solanum tuberosum L.) increases with increasing inhibitor concentration only to a limited extent, depending on the length of the tissue incubation with the inhibitor. In contrast to this, increasing concentrations of dinitrophenol have a rapid and total inhibitory effect on the active transport. Leucine transport in the same tissues is strongly inhibited by dinitrophenol but is not affected by cycloheximide, whereas incorporation into protein is mainly inhibited by cycloheximide. It appears that the mechanism of transport inhibition by cycloheximide in plant tissues consists in stopping new carrier synthesis and not in the disruption of energy flow. Sulfate carriers show comparable decay rates in barley roots and potato tuber, the mean life being shorter than that of the leucine carriers. These appear more stable in roots than in storage tissues.

Journal Article↗
PubMed1969

Inhibition of arbovirus assembly by cycloheximide.

Addition of cycloheximide (100 mug/ml) to cultures of chick cells infected with Semliki Forest virus (SFV) halted subsequent increase in virus titers. When added after 4 hr of infection, the drug had no effect on the rate of viral ribonucleic acid (RNA) synthesis, although marked inhibition of protein synthesis was seen. All of the previously identified forms of SFV RNA were seen in the drug-treated cells at higher concentrations than were present in untreated controls. The latter observation appeared to result from a failure to form viral "cores" or nucleocapsids in the cycloheximide-treated cells, resulting in sequestration of viral RNA intracellularly. The failure to form new virus cores was correlated with the failure of type II cytopathic vacuoles to appear in thin sections. Virus budding from the cell surface and the formation of type I cytopathic vacuoles persisted in cycloheximide-treated cells. The cellular pool of the major protein present in the virus core appeared to be small. None of this protein was found in a free pool in cytoplasm. The results indicated that, in the presence of cycloheximide, virus assembly was impaired because of the small size of the cellular pool of the major protein required for virus core formation.

Journal Article↗
PubMed1996

MK-801 induces apoptotic neuronal death in the rat retrosplenial cortex: prevention by cycloheximide and R(-)-2-hexyl-N-methylpropargylamine.

MK-801 is a non-competitive N-methyl-D-aspartate (NMDA) receptor antagonist which can prevent excitatory neuronal death. At higher concentrations, however, it can also induce neuronal death in the limbic system. This MK-801-induced selective neuro-toxicity has been proposed as an animal model for dementia and psychosis. We have investigated the effects of the protein synthesis inhibitor cycloheximide and the neurorescue agent 2-hexyl-N-methylpro-pargylamine [R(-)-2HxMP] on MK-801-induced neuronal death in the retrosplenial cortex in the rat. Cycloheximide [2 mg/kg, subcutaneously (sc)] administered either 1 hr before, or after, injection of MK-801 (5 mg/kg, sc) prevented almost completely neuronal shrinkage and nuclear condensation of the granular retrosplenial cortex as assessed by hematoxylin-eosin staining. The results suggest that the MK-801-induced neuronal death was apoptotic. This neurorescue effect by cycloheximide was time dependent: after 4 hr the effect was reduced to about 50% and by 8 hr had disappeared. R(-)-2HxMP (0.25 mg/kg, sc), which does not inhibit protein synthesis in vitro, was also found to be effective at preventing MK-801-induced neuronal death.

Animals↗
PubMed1975

Morphological effects of a large single dose of cycloheximide on the intestinal epithelium of the rat.

Adult male rats received 15 mg/kg cycloheximide and the subsequent morphological effects at three and six hours after injection were evaluated using histometry, light and electron microscopy, histological demonstration of terminal web and acid phosphatase, and radioautography with tritiated thymidine. Rapid atrophy of the villi took place, progressing from the villus tip by premature exfoliation of epithelial cells. The crypts also diminished by random exfoliation of many crypt cells and by partial or complete disintegration. Mitosis and epithelial cell migration were absent. By six hours, the area occupied by the villi and the crypts per unit length of histological section was decreased by about 70-90% in most of the small intestine but only by about 40-60% in the duodenum and the terminal ileum. In the upper half of the villi, the epithelium was strongly positive for acid phosphatase and contained large numbers of round bodies resembling primary lysosomes. In the lower half, the microvillous border and terminal web were found to be disrupted. Animals receiving only 5 mg/kg cycloheximide also showed the atrophy of villi and crypts, and the round bodies resembling lysosomes. Evidence from several sources has indicated that protein synthesis in normal villus epithelial cells subsides toward the villus tip and becomes minimal at exfoliation. At exfoliation, proteins responsible for epithelial cohesion probably fail because they are no longer replenished. Cycloheximide appears to accelerate this process.

Animals↗
PubMed1996

The translational inhibitor cycloheximide represses growth factor depletion-induced apoptosis in an alb-SV40T transgenic rat liver cell line.

A transgenic rat line carrying the alb-SV40A transgene has been described by this laboratory. Several cell lines have been established from the livers of two of these rats. One of these cell lines, L37, exhibits a large nuclear/cytoplasmic ratio and a well-differentiated cytoplasm containing numerous organelles. When L37 cells are placed into culture medium lacking necessary growth factors, cellular proliferation continues for 48 hours after medium change. Subsequent to the initial 48 hours, cells begin to shrink and lose contact with adjacent cells, eventually sloughing off the culture plate surface, with most cell deaths occurring between 48 and 96 hours after medium change. Microscopic examination of sloughing cells indicates they possess highly convoluted and blebbed plasma membranes, a morphological characteristic of apoptosis. Ultrastructural studies demonstrate the ubiquitous presence of apoptotic bodies. When DNA isolated from growth factor-depleted cells is resolved on agarose gels, DNA fragmentation ladders are observed at times of maximum apoptotic change. Quantitative analysis of L37 cells between 48 and 96 hours after the removal of the culture medium shows that 59% +/- 2% of the cells undergo apoptosis. When cycloheximide, puromycin, or actinomycin D is added to the L37 cultures, only cycloheximide is able to repress apoptosis, indicating that the mechanism of apoptosis in the L37 liver-derived cell line requires a cycloheximide-sensitive translational event. The extremely high rate of apoptosis, together with the maintenance of hepatocellular characteristics, indicates the usefulness of this cell line as a model in which to study the mechanisms of hepatocellular apoptosis.

Albumins↗
PubMedDate not supplied

Transferrin secretion in response to different modes of FSH stimulation and cycloheximide in superfused Sertoli cell cultures.

The influence of different modes of FSH stimulation and cycloheximide on transferrin secretion by rat Sertoli cells was investigated using a superfusion culture system. Sertoli cells from 18-day-old rats were cultured in serum-free medium on Matrigel-covered slides first in static conditions for 19 hours, and then superfused at a flow rate of 2.5 ml/hour. After an equilibration period of 48 hours to establish the basal rate of transferrin secretion, the cultures were exposed to various modes of FSH stimulation. Sertoli cells stimulated intermittently (20 min/2 hours) up to 22 hours responded to each consecutive FSH pulse with a rapid increase of transferrin secretion followed by a decline toward basal values. Continuous 22-hour exposure to FSH elicited an immediate increase followed by irregular fluctuations and a transient decline towards the baseline. With either mode of FSH stimulation, there was a secondary prolonged increase in transferrin secretion. Although cultures stimulated intermittently or continuously during the entire experimental period (22 hours) secreted similar cumulative amounts of transferrin (10.8 +/- 0.5 micrograms and 11.1 +/- 0.8 micrograms, respectively), there was a direct correlation between the secreted amount of transferrin and the duration of FSH exposure up to 8 hours. Addition of cycloheximide decreased both basal and FSH-stimulated transferrin secretion. However, even when cycloheximide was added 1 hour before FSH, an early secretory peak in response to FSH was still observed.(ABSTRACT TRUNCATED AT 250 WORDS)

Animals↗
PubMed2004

Superinduction of IL-6 by cycloheximide is associated with mRNA stabilization and sustained activation of p38 map kinase and NF-kappaB in cultured caco-2 cells.

Protein synthesis inhibitors paradoxically increase the expression of early-gene products, including various cytokines, through a process known as superinduction. Superinduction is cell-specific and the mechanisms involved are not fully understood but are usually attributed to decreased mRNA degradation. There is, however, increasing evidence that activation of signaling cascades and increased transcriptional activation may be involved as well. Recent studies suggest that IL-6 production in the intestinal mucosa is particularly important due to its anti-inflammatory and protective effects. The effect of protein synthesis inhibitors on IL-6 production in enterocytes, however, is unknown. Treatment of Caco-2 cells with cycloheximide (10 microg/ml) increased IL-6 mRNA and protein levels in IL-1beta-treated cells and this was associated with increased mRNA stabilization. In addition, cycloheximide suppressed IkappaBalpha resynthesis and prolonged p38MAP kinase activation and these changes were associated with sustained activation of the transcription factor NF-kappaB. NF-kappaB activation, in turn, was prevented by the specific p38MAP kinase inhibitor SB208350. Our results suggest that superinduction of IL-6 by cycloheximide in enterocytes results from both increased mRNA stabilization and upregulated transcriptional activity mediated by prolonged activation of the p38 MAP kinase and NF-kappaB.

Blotting, Western↗
PubMed1985

Superinduction by cycloheximide of mitogen-induced secreted proteins produced by Balb/c 3T3 cells.

We describe here some of the characteristics of the regulation of a group of secretory proteins whose secreted levels rise within 2-4 h of adding fibroblast growth factor (FGF), epidermal growth factor (EGF), or serum to quiescent Balb/c 3T3 cells. The levels of these secretory proteins are regulated similarly to the interferons. When cycloheximide is present during the induction period, the amounts of [35S]methionine incorporated into five of these proteins that we have called "superinducible proteins" (SIPs) is increased 2-5-fold. Superinduction of the SIPs is seen also in response to polyribol-polyriboC, the classical inducer of interferons. None of the SIPs, however, are immuno-precipitated by anti-beta-interferon antibody. Induction and superinduction of the SIPs is inhibited by actinomycin D. Superinduction occurs at concentrations of cycloheximide that inhibit protein synthesis by at least 85%. The SIPs are not major intracellular proteins; they are barely detectable in cellular fractions. Their induction is, however, correlated with the ability of the polypeptide growth factor to stimulate DNA synthesis; EGF, FGF, and serum induce the SIPs, whereas insulin does not, and insulin alone weakly stimulates DNA synthesis in these cells. Because FGF, EGF, and serum cause the SIPs to be produced at concentrations of cycloheximide that inhibit 85% of bulk protein and DNA synthesis, it follows that the SIPs are produced directly from the action of the growth factor and not as a consequence of increased growth. Although probably not interferons, in analogy to the lymphokines, the SIPs could be a set of autocrine or paracrine factors that rapidly convey the growth or differentiation signal between cells.

Animals↗
PubMed1995

Activation of murine oocytes with Ca2+ ionophore and cycloheximide.

A Ca2+ ionophore (A23187, 3 microM) and inhibitor of protein synthesis (cycloheximide, 10 micrograms/ml) were used sequentially as a unique method for activating mouse oocytes in vitro. Brief exposure of oocytes to A23187 followed by 6 hr in cycloheximide resulted in a higher activation rate (93.8%) compared to A23187 or cycloheximide alone (37.7% and 36.5%, respectively) or the two reagents in reverse order (29.8%). The parthenogenones consistently contained a single pronucleus and second polar body, and showed a high degree of developmental potential, as assessed by transfer to recipient females or addition of a male pronucleus followed by transfer to recipients. This method is a useful way of obtaining large numbers of activated haploid mammalian oocytes for further developmental studies.

Animals↗