The effects of bromocriptine on neuroleptic‐induced endocrinological disturbances (amenorrhea, galactorrhea and impotence) were investigated. Bromocriptine (5.0‐7.5 mg/day) was administered to psychiatric patients receiving neuroleptics and developing hyperprolactinemia. The following results were obtained.
1. Menses recurred in 7 of 10 patients with amenorrhea.
2. A decrease in lactation appeared in 5 of 6 patients with galactorrhea.
3. A significant increase in the serum levels of testosterone was observed after 8 weeks of the treatment in male patients. (N = 6)
4. There was no remarkable deterioration in regard to the psychotic symptoms in schizophrenic patients. (N = 7)
5. In non‐schizophrenic patients (N = 9), a significant improvement was observed in regard to “somatic concern” (in Brief Psychiatric Rating Scale).
Effects of betahistine, an antivertigo drug, were examined on the lateral vestibular nucleus (LVN) neurons of cats anesthetized with alpha-chloralose. Spike generation of monosynaptic LVN neurons elicited by vestibular nerve stimulation remained unaffected with intravenous administration of betahistine up to 5 mg/kg and with iontophoretic application of the drug up to 200 nA. In contrast, the spike generation of polysynaptic I neurons in the LVN was dose-dependently inhibited by intravenous as well as iontophoretic application of betahistine. These results suggest that small doses of betahistine more selectively interfere with synaptic transmission in the polysynaptic I neurons than in the monosynaptic neurons.
Water intoxication occurs almost exclusively in many patients with chronic psychiatric disorder. To elucidate the mechanism of this syndrome, we undertook the following animal experiments and clinical study.
Twelve rabbits were given neuroleptics for eight weeks. From measurement of arginine vasopressin (AVP) secretion response to osmotic stimuli (fluid deprivation, partaking ad lib. and water loading), we found that chronic neuroleptic administration might raise the sensitivity of AVP escretion response.
Then we investigated the manners of AVP secretion during ad lib. drinking in seventeen schizophrenic patients with hyponatremia and sixteen schizophrenic patients without hyponatremia. Normal range of plasma AVP was obtained from healthy volunteers by water loading. Only in both schizophrenic groups was plasma AVP detected below 270 mosm/kg osmolality. We observed that sensitivity of AVP secretion response to osmolality was decreased in schizophrenic patients, regardless of the presence of hyponatremia.
We hypothesize that the primary low sensitivity of AVP secretion response to osmo‐receptor and the secondary renal hypersensitivity of AVP receptor may play the major role in the occurrence of water intoxication, Linked to SIADH, in schizophrenic patients.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.