Search PubMed⌕ Search

SEARCH · Search PubMed

Results for “ANOSMIA”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 577 records · Page 32Linked to original sources

Interactions of testosterone with the olfactory system in the display of mounting behavior in the female rat.

Adult ovariectomized female rats received a testosterone propionate (TP) silastic implant (day 0) and were subsequently tested for mounting behavior. The number of females displaying mounting behavior increased from day 2 (0%) to day 14 (94%) following testosterone implantation. Olfactory bulbectomy (OB) performed on day -7 or on day +14 reduced the number of females that mounted on day +16 as compared to sham counterparts. However, the number of females displaying mounting behavior was significantly higher when OB was performed on day +14 than on day -7. Peripheral anosmia induced by ZnSO4 instillation, either with multiple instillations beginning on day -8 before TP implant or with a single injection on day +14, equally impaired mounting behavior on day +16. These results, which further confirm the role of the olfactory system in facilitating the display of mounting behavior in the female rat, suggest an olfaction-testosterone interaction.

Animals↗

Olfactory recognition of infants in laboratory mice: role of noradrenergic mechanisms.

Noradrenaline depletion of the olfactory bulbs induces cannibalism at parturition in primiparous mice, without producing anosmia or impairment of maternal behaviour. Similar lesions made in multiparous experienced females do not result in cannibalism. The present studies investigated 1) whether a 30-min exposure to pups or to distal cues from pups given to virgin females before noradrenaline depletion of the olfactory bulbs overcame the impairment in recognition at first parturition, and 2) whether noradrenaline-depleted females allowed to care for their pups for the 24 h following parturition showed a failure in recognition on a second parturition. Experiment 1 showed that exposure to distal cues from pups enabled the females to successfully recognize pups at parturition in comparison to naive females. However, neither the exposure to pup cues nor the fully interactive experience with pups overcame the disruptive effect on recognition at birth of the noradrenaline depletion. In Experiment 2, we found that olfactory recognition was impaired in noradrenaline-depleted females on second parturition, in spite of the mothering experience with their own pups.

Animals↗

Peripheral olfactory deafferentation of the primary olfactory system in rats using ZnSO4 nasal spray with special reference to maternal behavior.

A modified method of applying ZnSO4 to the olfactory mucosa is described. Treated rats experienced severe nasal congestion that cleared within 24 h; more persistent morbidity did not occur. Nonpregnant females observed with male intruders 24 h following ZnSO4 showed no alterations in behavior other than a reduction in anogenital sniffing, indicating that they were not hypoactive or irritable. In other experiments, lactating females were observed in a hole-board apparatus; 2 days posttreatment anosmia was confirmed in 80% of bilaterally ZnSO4-treated females by the absence of preference for pup odors. After bilateral but not unilateral ZnSO4 treatment, initially activity scores and nose pokes were equivalent in all groups, but later they both were lower than in controls, probably due to a more rapid habituation to the novel apparatus. We conclude that intranasal ZnSO4 by small-volume spray is a useful experimental tool.

Administration, Intranasal↗

Functional deficits produced by 3-methylindole-induced olfactory mucosal damage revealed by a simple olfactory learning task.

Methods for assessing functional consequences of olfactory mucosal damage were examined in rats exposed to 3-methylindole (3-MI). Treatment with 3-MI (400 mg/kg) induced severe degeneration of olfactory sensory epithelium followed by regeneration, fibrous adhesions, and osseous remodeling of the nasal passages. At 100 mg/kg, there was mild Bowman's gland hypertrophy while the sensory epithelium remained intact. Rats receiving 3-MI demonstrated a treatment-related deficit in acquiring an olfactory learning task which was not due to altered cognitive abilities, as determined by subsequent testing in a step-through passive avoidance task. The results confirm the conclusion that alterations in functional indices resulted from 3-MI-induced anosmia and demonstrate the utility of simple learning tasks in assessing functional capacity following olfactory epithelial damage in rats.

Animals↗

Giant basal prolactinoma extending into the nasal cavity.

An unusual case of a giant prolactinoma extending to the nasopharynx and nasal cavity is presented. A 35-year-old man admitted for nasal obstruction and visual disturbances was found to have bilateral anosmia, right homonymous hemianopsia, and a right hemiparesis. The serum prolactin level was 13,300 ng/mL. Radiological examination revealed a large mass invading the skull base and extending into the suprasellar region and the left frontal lobe superiorly and into the nasopharynx inferiorly. Subtotal removal was done through a bilateral orbitofrontal craniotomy, which was followed by radiotherapy and bromocriptine administration. Immunohistochemical analysis confirmed a prolactinoma. The rarity of such a tumor, its location and extension, and the usefulness of magnetic resonance imaging and immunohistochemistry are stressed. Pertinent literature is reviewed.

Adult↗

Hypothalamic and pituitary function in hypogonadotropic hypogonadism.

Hypogonadotropic hypogonadism has been identified as a cause of partial or complete failure of puberty, may be familial and may have other associated abnormalities of hyposmia, intellectual retardation, perceptive deafness, color blindness, skeletal deformities, and gynecomastia. Pituitary function is usually normal with the primary defect believed to be hypothalamic. A twenty-year-old white male with a clinical diagnosis of hypogonadotropic hypogonadism and anosmia under-went complete endocrine evaluation with evaluation of the pituitary response to luteinizing hormone-releasing hormone. FSH (follicle-stimulating hormone) and LH (luteinizing hormone) release after luteinizing hormone-releasing hormone did occur, but the response was less than that seen in normal controls. Evaluation demonstrated that the pituitary-gonadal axis was intact with the hypothalamic-pituitary axis being defective. Therapy with the synthetic decapeptide (luteinizing hormone-releasing hormone) is correct theoretically and may be superior to therapy with exogenous gonadotropins.

Adult↗

The candidate gene for the X-linked Kallmann syndrome encodes a protein related to adhesion molecules.

Kallmann syndrome associates hypogonadotropic hypogonadism and anosmia and is probably due to a defect in the embryonic migration of olfactory and GnRH-synthesizing neurons. The Kallmann gene had been localized to Xp22.3. In this study 67 kb of genomic DNA, corresponding to a deletion interval containing at least part of the Kallmann gene, were sequenced. Two candidate exons, identified by multiparameter computer programs, were found in a cDNA encoding a protein of 679 amino acids. This candidate gene (ADMLX) is interrupted in its 3' coding region in the Kallmann patient, in which the proximal end of the KAL deletion interval was previously defined. A 5' end deletion was detected in another Kallmann patient. The predicted protein sequence shows homologies with the fibronectin type III repeat. ADMLX thus encodes a putative adhesion molecule, consistent with the defect of embryonic neuronal migration.

Amino Acid Sequence↗

Hypothyroidism disrupts neural development in the olfactory epithelium of adult mice.

Adult mice made hypothyroid with propylthiouracil (PTU) lose their sense of smell. This is prevented by daily administration of thyroxine. As thyroxine is necessary for the correct development of the nervous system it may also be necessary for the genesis of new olfactory receptor neurones, a process that continues into adulthood. Adult mice were treated with PTU, injected with [3H]thymidine after 54 days and killed 5 or 15 days later. Microscopic analysis of the olfactory epithelium after autoradiography revealed similar numbers of labelled nuclei in the basal cell layer of the olfactory epithelia of Control and Hypothyroid mice 5 days after injection with [3H]thymidine. This indicated similar rates of basal cell division in the two groups. Fifteen days after [3H]thymidine injection, however, there were fewer labelled nuclei in the receptor cell layer of Hypothyroid mice and the olfactory epithelium was thinner than in Controls. Thyroxine therapy which reversed PTU-induced anosmia also reversed the epithelial effects of PTU treatment. Somewhat unexpectedly, there were no differences between the treatment groups in the average diameter of glomeruli in the olfactory bulb, and no differences in the expression of olfactory marker protein. The results indicate that although hypothyroidism disrupts neural development in the olfactory epithelium, it does not lead to a complete loss of mature receptor neurones.

Animals↗

Effect of local 6-OHDA and 5,6-DHT injections into the rat olfactory bulb on neophobia and learned aversion to a novel food.

This study investigated the role of the noradrenergic (NA) and the serotoninergic (5-HT) centrifugal fibers on the olfactory bulb (OB). For this purpose, behavioral responses largely depending on olfactory information were measured in rats after discrete bilateral injections into the OB with either 6-hydroxydopamine (6-OHDA) or 5,6-dihydroxytryptamine (5,6-DHT) solutions. The evaluation of the level of endogenous 5-HT in the OB was measured by high performance liquid chromatography. The NA fibers appeared lesioned after the 6-OHDA treatment only, whereas the 5-HT level was significantly reduced in 5,6-DHT treated bulbs only (34% of the control value). The animals were fed on usual stock-diet (S) and had the choice between S and a novel food (V) on neophobia test, and again on the following day after aversive conditioning (0.9 mEq/kg LiCl i.p.). The behavioral results showed that the drug administrations were followed by a significant effect in one case only: the intake of V was significantly enhanced in 6-OHDA treated animals during neophobia test. Thus, neophobia was reduced by 6-OHDA. The data are interpreted as follows: (1) the lesion of the bulbar NA or 5-HT fibers does not induce total anosmia; and (2) the NA innervation of the OB could play a role in the modulation of behavioral responses to biological odorants.

5,6-Dihydroxytryptamine↗

Luteinizing hormone-releasing hormone (LHRH)-expressing cells do not migrate normally in an inherited hypogonadal (Kallmann) syndrome.

Kallmann syndrome inherited hypogonadotropic hypogonadism with anosmia, is associated with an X-chromosome deletion at Xp 22.3. In a Kallmann fetus, we have found an absence of luteinizing hormone-releasing hormone (LHRH)-expressing cells in the brain despite dense clusters of LHRH cells and fibers in the nose. LHRH-containing cells and neurites end in a tangle beneath the forebrain, within the dural layers of the meninges, on the dorsal surface of the cribriform plate of the ethmoid bone. Normal fetal brains, matched for age and sex, had LHRH cells and fibers, as expected, in the hypothalamus and preoptic area. Since LHRH-expressing cells recently were discovered to migrate from the olfactory placode into the brain, it appears that the hypogonadotropism of the Kallmann syndrome can be accounted for by a failure of LHRH cells to migrate into the brain.

Brain↗

Giant intracranial mucocele.

A 21-year-old man was admitted to hospital because of recent anosmia and liquorrhoea. He also complained of moderate headache and concentration problems in the past few years. On CT scan and MRI scans a big subfrontal process was seen, partially solid and partially cystic. Neurosurgical and histological findings proved that the lesion was an osteoma of the anterior skull base, concomitant with an intradurally extending mucocele.

Adult↗

The effects of beta-endorphin infusions into the amygdala on visual and olfactory sensory processing during sexual behaviour in the male rat.

Sexually experienced male rats infused bilaterally into the amygdala with 60 pmol beta-endorphin show decreased rate of precopulatory investigation of the female and delayed intromission latency, but copulation is left unaltered. Such males are still able to discriminate between the odours of bedding from receptive and unreceptive females, demonstrating that beta-endorphin does not impair the ability to detect sexually relevant odours. Preventing visual cues emitted by females during proceptive behaviour (by treating them with haloperidol) delayed intromission latency but had no effect on preintromission investigation. Intra-amygdaloid beta-endorphin exacerbated the effects of this treatment on the intromission latency. Inducing anosmia in males (by applying zinc sulphate solution to the olfactory mucosa) decreased their anogenital investigation and delayed their intromission latency. These effects were not enhanced by intra-amygdaloid beta-endorphin. Allowing males to investigate and initiate the first intromission prior to intra-amygdaloid infusion had no effects on subsequent intromissions. However, if following an intromission with one female and an infusion of beta-endorphin, the male was presented with an unfamiliar female then the effects of intra-amygdaloid beta-endorphin on investigation and intromission returned. These results suggest that beta-endorphin in the amygdala interferes with the processing of female-specific olfactory information. Without this processed information, classification of the female as a sexual stimulus may be impeded and thus sexual arousal delayed.

Amygdala↗

Differential effects of cocaine, alcohol, and nicotine dependence on olfactory evoked potentials.

Olfactory evoked potentials (OEP) were elicited by odorous and nonodorous stimuli in 50 adult subjects: 26 subjects with histories of either cocaine (n = 19) or alcohol (n = 7) dependence, 10 with histories of nicotine but no other drug dependence, 2 with clinical anosmia of peripheral origin, and 12 subjects without drug or olfactory disorders. The presentation of nonodorous stimuli (i.e. a nasal air puff) did not elicit OEP component amplitude and latency differences among the groups. However, the presentation of odorous stimuli elicited a significantly smaller P1 component in the cocaine-dependent and alcohol-dependent groups than in the normal control and nicotine-dependent groups. The P1 amplitude deficit in the cocaine-dependent group is consistent with case report data associating cocaine use with lesions of the peripheral and/or central olfactory apparatus.

Adult↗

Isolation and characterization of the gene responsible for the X chromosome-linked Kallmann syndrome.

Kallmann de Morsier Syndrome is defined by the association of an hypogonadism with an anosmia. The hypogonadism is due to a deficiency of GnRH (gonadotropin-releasing hormone). Olfactory bulbs and tracts are underdeveloped in the patients. Embryological studies have indicated that the migration of GnRH neurons and the axonal extension of olfactory neurons, which both originate in the olfactory epithelium during embryogenesis, were impaired in a fetus affected by X-linked Kallmann Syndrome. By a positional cloning strategy, we have isolated the KAL gene, responsible for the X-linked form of the disease. The gene consists of 14 exons. A highly homologous pseudogene on the Y chromosome has been characterized. The KAL gene encodes a putative secreted protein of 680 amino acids, which contains four fibronectin type III repeats and a four disulphide core motif. The former motif is usually associated with adhesion function. The latter has been described in protein with antiprotease activity. We have isolated the chicken KAL homologue and studied its expression by in situ hybridization during late embryonic development. The gene is expressed in various neuronal populations of the central nervous system, including mitral cells of the olfactory bulbs. We suggested that the KAL protein might be involved in late neuronal differentiation.

Animals↗

Molecular heterogeneity of steroid sulfatase deficiency: a multicenter study on 57 unrelated patients, at DNA and protein levels.

Steroid sulfatase (STS) deficiency is the biochemical defect of X-linked ichthyosis (XLI), one of the most common X-linked disorders. We studied 57 European unrelated patients affected by STS deficiency. Twenty-eight patients were from Italy, 24 from the United Kingdom, 4 from The Netherlands, and 1 from Denmark. In two families XLI was associated with Kallmann syndrome (hypogonadotropic hypogonadism and anosmia). STS enzymatic activity was profoundly deficient in all cases. Direct DNA analysis, using cDNA and genomic probes from the STS gene and linked regions, demonstrated heterogeneity of the molecular defect. Forty-eight patients (84%) showed a deletion of the STS gene. In 44 cases the deletion also involved the STS flanking locus DXS237. In 1 patient a partial deletion of the STS gene was detected and in 9 patients no evidence of deletion was found. Locus DXS31 (probe M1A), previously mapped to Xp22.3-pter, was not deleted either in 24 patients with X-linked ichthyosis or in two families with X-linked ichthyosis associated with Kallmann syndrome. Consequently, the following loci order could be suggested: telomere--DXS31--(DXS237, STS)--Kallmann--centromere. Immunoblotting experiments, performed using anti-STS polyclonal antibodies, revealed the absence of cross-reacting material to STS in all cases tested, including 4 patients without evidence of deletions.

Arylsulfatases↗

Sensory neurotoxicology: use of the olfactory system in the assessment of toxicity.

Although many compounds are purported to cause olfactory dysfunction, little experimental research has been done in this area. The nasal epithelium, being one of the first "wet tissues" to come into contact with airborne compounds, should be a good indicator of toxic insult. The same general procedures used to measure visual or auditory function can be applied to the olfactory system, although olfactory stimuli are much more difficult to generate and control. Cadmium exposure, which is frequently cited as causing olfactory dysfunction in humans, did not produce anosmia (loss of smell) in rats, even though there was a large increase in cadmium levels in their olfactory bulbs. Rats exposed to methyl bromide showed a severe disruption in olfactory function as well as in morphology and neurochemical indices. However, functional recovery occurred even in the presence of continuing morphological and neurochemical evidence of damage. A nonsensory function of the olfactory system, transneuronal transport via the primary sensory neurons, may represent a mechanism of entry into the central nervous system for compounds that are normally excluded by the blood-brain barrier.

Administration, Intranasal↗

Effects of inhalation of cadmium on the rat olfactory system: behavior and morphology.

To investigate the effects of cadmium on olfaction, two separate studies were conducted in which male adult rats were exposed to CdO, via inhalation, for 5 h per day, 5 days a week for 20 weeks. Target exposure values of 250 and 500 micrograms/m3 were measured at 200 and 325 micrograms/m3 for the low concentration in two experiments, and 550 and 660 micrograms/m3 for the high concentration. Prior to exposure, olfactory thresholds were obtained using a conditioned suppression technique. After 20 weeks of cadmium exposure, there was no evidence of anosmia in any of the rats nor were there any significant changes observed in olfactory thresholds. Although olfaction was not impaired, cadmium levels in the olfactory bulbs of exposed rats were significantly elevated compared to controls. Cardiac and respiratory histopathology were observed at all exposure levels, but there was no evidence of nasal pathology related to exposure to cadmium. Failure of cadmium to produce olfactory dysfunction may be due to the protective effects of metallothionein and/or to the highly resilient nature of the rodent olfactory system.

Administration, Inhalation↗

The Kallmann's syndrome variant (KSV) model of the schizophrenias.

The KSV model of the schizophrenias proposes that up to 70% of schizophrenics have a pathogenic allele, or abnormal expression, of the KALIG-1 gene which is located at Xp22.3. This gene encodes a nerve-cell adhesion molecule (N-CAM) like protein, and is deleted in 66% of patients with Kallmann's syndrome, anosmia with secondary hypogonadism. Although superficially distinct, the schizophrenias and Kallmann's syndrome show numerous parallel trait defects which occur with a similar sex distribution. These defects are usually more profound in Kallmann's syndrome. Occasionally, Kallmann's patients exhibit additional defects, such as ichthyosis, which are due to the further deletion or translocation of adjacent genes. Since schizophrenics exhibit virtually all known trait defects in Kallmann's except these, it suggests that the aberrant genes are defective, but not deleted in schizophrenia. It also appears that compensatory mechanisms, involving serine proteases, are active in schizophrenia, which largely preserve fertility, but at the expense of an increased vulnerability to develop a psychosis by an episodic disruption of the blood-CSF barrier. Consequently, schizophrenia is rare in Kallmann's patients, while most schizophrenics are capable of reproduction.

Alleles↗