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V Luine

Publications and source records attributed to V Luine.

24 records · Page 2Linked to original sources
PubMed1986

Observations in a preliminary open trial of estradiol therapy for senile dementia-Alzheimer's type.

Previous studies have suggested that estrogen may have an effect on cognitive and emotional function in women. Studies in rodents and non-human primates have demonstrated the presence of estrogen receptors in brain, and that estrogen can affect behavior in animals. Estrogen administration to ovariectomized rats increases choline acetyltransferase activity in certain regions of brain. Choline acetyltransferase activity is known to be significantly decreased in senile dementia-Alzheimer's type (SDAT). Based on these observations, we treated seven women with SDAT with low dosages of estradiol over a six week period. A battery of assessments was performed throughout the study period. Significant improvements in three women were noted on measures of attention, orientation, mood and social interaction. These estrogen-responsive women were characterized by dementia associated with an affective disorder, older age at onset, and evidence of osteoporosis. Side effects of estradiol therapy included withdrawal bleeding in one woman and transient breast tenderness in another. Estradiol therapy thus may benefit some postmenopausal women with SDAT. The occurrence of osteoporosis in the estrogen-responsive group suggests that SDAT in some women may be associated with or related to a systemic estrogen deficiency state. However, considering the potential for serious side effects as a result of estrogen therapy, the current risk to benefit ratio precludes the routine clinical use of estrogen for dementia until careful clinical research trials have been performed.

Aged↗
PubMed1985

Intrahypothalamic 5,7-dihydroxytryptamine: temporal analysis of effects on 5-hydroxytryptamine content in brain nuclei and on facilitated lordosis behavior.

The long-term relationship between serotonin (5-HT) levels in discrete hypothalamic nuclei and female rat sexual behavior, the lordosis response, was examined following intrahypothalamic injection of 5,7-dihydroxytryptamine (5,7-DHT). One week following 5,7-DHT injection, 5-HT levels in the ventromedial hypothalamic nucleus, dorsomedial nucleus, anterior hypothalamic nucleus and the medial preoptic nucleus were approximately 90% depleted as compared to sham animals. Other hypothalamic and preoptic areas including the arcuate-median eminence, vertical nucleus of diagonal band and lateral septal nucleus showed smaller reductions in 5-HT, from 40 to 70% of sham values. At this time estrogen-dependent lordosis behavior in the lesioned group was facilitated. Behavioral facilitation was greatest at 4 weeks post lesion when depletion of 5-HT in the VMN was maximal. 5-HT levels increased at 57 days after 5,7-DHT treatment in most areas, and by 71 days post lesion, no significant differences in 5-HT levels were found between sham and 5,7-DHT-treated groups. Concomitant with the increases in 5-HT, facilitated lordosis behavior gradually decreased. Loss of behavioral facilitation appeared to be most closely related to increases in content of 5-HT in the ventromedial nucleus. These results further support the hypothesis that 5-HT endings in the hypothalamus exert tonic inhibitory regulation over hormone-dependent lordosis in the female rat. They also indicate that regenerating 5-HT fibers in the hypothalamus can reinstate a normal pattern of hormone-dependent behavioral function.

5,7-Dihydroxytryptamine↗
PubMed1982

Differential effects of catechol estrogens, progestins and CI-628 administered by constant infusion on the central and peripheral action of estradiol.

By means of continuous infusion by Alzet minipumps, we tested the ability of the catechol estrogens, 2-hydroxyestrone (2-OHE1) and 2-hydroxyestradiol (2-OHE2), as well as two progestins and the anti-estrogen, CI-628, to block the action of estradiol (E2) on sexual behavior, LH surge frequency, uterine weight increase and glucose-6-phosphate dehydrogenase (G6PDH) activity in the uterus and pituitary of ovariectomized rats. Neither catechol estrogen produced inhibitory effects, whereas the potent progestin, R-5020 (5 micrograms/h), and CI-628 (50 micrograms/h) inhibited the E2-induced increase in the LH surge frequency and lordosis response. Progesterone at 20 micrograms/h and CI-628 at 5 micrograms/h did not influence these end points. In the pituitary and uterus, the concurrent administration of R-5020 and E2 attenuated the increase of G6PDH activity. As expected, CI-628 inhibited the action of E2 on G6PDH but was more effective in doing so at the lower of the two doses. CI-628 (50 micrograms/h) also blocked the neuroendocrine and behavioral effects of 2-OHE2 (1 microgram/h) and 4-hydroxyestradiol (0.1 microgram/h). Taken together with our previous studies, these results are consistent with the notion that the catechol estrogens exert effects on sexual behavior and LH surge frequency by virtue of their estrogenic properties rather than by other means.

Animals↗
PubMed1980

Androgen affects cholinergic enzymes in syringeal motor neurons and muscle.

We examined the role of testosterone (T) in regulating the weight of the songbird syrinx and the activity of two cholinergic enzymes, choline acetyltransferase (CAT) and acetylcholinesterase (AChE). Castration of adult male zebra finches or neonatal canaries results in a lowering of syringeal weight and CAT and AChE activity. Administration of T for 1-4 weeks restores syringeal weight and AChE to intact levels in male zebra finches. Activity of CAT in muscle is not fully restored. Ovariectomy of female zebra finches and canaries does not affect these syringeal parameters, but T administration to ovariectomized females for 1 month increases syringeal weight and AChE activity. In the zebra finch tracheosyringealis nerve, activity of CAT and AChE is decreased one month after castration. T administration to castrates maintains nerve AChE activity but not CAT. In contrast to changes in the syrinx, tongue muscles do not change in weight or enzyme activity when circulating T levels are altered. Effects of muscle use and disuse were found on syringeal weight and AChE activity, but an androgenic effect also operates in addition. Results suggest that one mechanism for T regulation of singing in passerine birds is through induction of specific enzymatic proteins in androgen target neurons and muscles.

Acetylcholinesterase↗