Eur J Pharmacol. 1995 Apr 4;276(3):281-4.
Differential effects of WAY-100135 on the decrease in 5-hydroxytryptamine release induced by buspirone and NAN-190.

Routledge C, Gurling J, Ashworth-Preece MA, Dourish CT.

Department of Neuropharmacology, Wyeth Research, Maidenhead, Berkshire, UK.

1-(2-Methoxyphenyl)-4-[(phthalimido)butyl] piperazine (NAN-190) and 8-[4-[4-(2-pyrimidinyl)-1-piperazinyl]butyl]-8-azaspiro[4.5] decane-7,9-dione (buspirone) are 5-HT1A receptor partial agonists which decrease 5-hydroxytryptamine (5-HT) release in vivo. In order to assess whether these ligands decrease 5-HT release by stimulating 5-HT1A receptors we examined the ability of the selective 5-HT1A receptor antagonist N-tert-butyl 3-4-(2-methoxyphenyl) piperazin-1-yl-2-phenylpropanamide dihydrochloride (WAY-100135) to block their inhibitory effects on 5-HT. NAN-190 (0.1 mg/kg s.c.) and buspirone (1.0 mg/kg s.c.) significantly decreased extracellular levels of 5-HT in hippocampal dialysates. WAY-100135 (10.0 mg/kg s.c.) attenuated the effect of buspirone but had no significant effect on the NAN-190-induced decreased in 5-HT release. These data demonstrate that buspirone is an agonist at the somatodendritic 5-HT1A receptor but that the inhibitory effects of NAN-190 on 5-HT release may be mediated via a mechanism other than, or in addition to, 5-HT1A receptor agonism.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7601215&dopt=Abstract buspirone Buspar

otago.ac.nz

Benzodiazepines and the novel anxiolytic buspirone share a common capacity to relieve clinical anxiety but do not share any side effects. Anxiety releases stress hormones and, at moderate doses, anxiolytic benzodiazepines block this release. It is interesting, therefore, that buspirone and other 5-HT1A agonists release stress hormones at moderate doses. Both the U-shaped dose-response curve seen with buspirone in some animal tests of anxiety and its slow onset of clinical action could be attributed to this release of stress hormones. Metyrapone (200 mg/kg), an inhibitor of 11-beta-hydroxylase, was used in the present experiments as a form of chemical adrenalectomy and was combined with administration of corticosterone (1 mg) to produce rats with presumed approximately normal corticosterone levels but no capacity to release endogenous corticosterone. This treatment reduced the difference normally observed in the effects of chlordiazepoxide (5 mg/kg) and buspirone (0.37 mg/kg) on a fixed interval schedule particularly in the early part of the interval when release of behavioral inhibition would be expected to contribute most to the effects. These results are consistent with the previous suggestion of Johnston and File (8) that the anxiolytic action of buspirone may be counteracted by activation of the pituitary-adrenal axis. Corticosterone appears to be the most likely critical agent for this antagonist action in the present experiments, although CRF and ACTH are also possibilities. It is likely that there is a mutual functional opposition between endogenous anxiolytic factors and stress hormones.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8728538&dopt=Abstract buspirone Buspar




Alcohol Alcohol. 1996 Mar;31(2):149-56.
Buspirone as an inhibitor of voluntary ethanol intake in male rats.

Hedlund L, Wahlstrom G.

Department of Pharmacology, University of Umea, Sweden.

The effect of buspirone, a drug with mainly 5-HT1A-agonist activity, on voluntary ethanol intake was tested in a rat model of alcoholism. In this model the treatment consists of an injection of ethanol (2.0 g/kg) or saline once a week, preceded by a 24 h choice between water and ethanol (10% w/v). This weekly injection of ethanol reduces voluntary ethanol intake in male rats. Maximal inhibition is seen after 5-6 weeks. At this maximal inhibition buspirone or saline was injected prior to the voluntary 24 h intake of ethanol in both the ethanol- and saline-injected groups. The tested doses were 5 mg/kg (week 5) and 20 mg/kg (week 6). There was no reduction in ethanol intake in the buspirone-injected groups when compared with their corresponding controls. A second experiment with buspirone was performed during the evaluation period following treatment with ethanol. This treatment consisted of a choice between water and ethanol (10%, w/v) for 1 day each week, followed by an injection of ethanol 2.0 g/kg) and lasted for 52 weeks. During the evaluation period the rats had a continuous choice between ethanol and water for 37 weeks and no injections were given. In this situation, with a longer exposure to ethanol, a dose of 20 mg/kg of buspirone in week 90 reduced ethanol intake by approximately 40%, when compared with controls. The effect of this buspirone dose lasted at least a week. This indicates that the long-term exposure to ethanol in the second experiment induces changes that affect the serotonergic transmission, and that this changed neural system is involved in the regulation of voluntary ethanol intake.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8737010&dopt=Abstract buspirone Buspar




Brain Res Dev Brain Res. 1996 Apr 30;92(2):190-8.
Protective effects of maternal buspirone treatment on serotonin reuptake sites in ethanol-exposed offspring.

Kim JA, Druse MJ.

Neuroscience Program, Loyola University Chicago, Stritch School of Medicine, Maywood, IL 60153, USA.

Previous work in this laboratory demonstrated that in utero ethanol exposure is associated with abnormal development of the serotonergic system. Specific abnormalities included deficiencies of serotonin (5-HT) and its metabolites, and cortical 5-HT reuptake sites. The concentration of 5-HT1A receptors was also altered. The serotonin deficit was detected in the fetal ethanol-exposed brain, at an age when 5-HT would normally function as an essential trophic factor. Thus, it was hypothesized that the early 5-HT ethanol-associated deficit of an essential trophic factor (e.g. 5-HT) could contribute to subsequent developmental abnormalities in serotonergic neurons. In the present investigation we used quantitative autoradiography (QAR) to more fully characterize the developmental abnormalities in 5-HT reuptake sites in developing offspring of ethanol-fed rats. In addition, we attempted to overcome the potential negative impact of the ethanol-associated deficit of fetal 5-HT, by administering a 5-HT1A agonist, buspirone, to pregnant rats. These investigations demonstrated that postnatal (PN) 19 and/or 35 day ethanol-exposed offspring had a significant decrease in [3H]citalopram binding to 5-HT reuptake sites in the frontal cortex, parietal cortex, lateral hypothalamus, substantia nigra, medial septum, and striatum. In contrast, [3H]citalopram binding was increased in the dorsal raphe on PN5 and in the median raphe on PN19. No significant ethanol-associated changes were detected in the hippocampus CA3 region or in the amygdala. When [3H]citalopram binding was compared in the offspring of saline- and buspirone-treated dams, it appeared that maternal treatment with buspirone prevented or reversed most of the ethanol-associated developmen




Int Arch Allergy Immunol. 1995 May-Jun;107(1-3):437-8.
Buspirone inhibits contact hypersensitivity in the mouse.

McAloon MH, ChandraSekar A, Lin YJ, Hwang GC, Sharpe RJ.

Arcturus Pharmaceutical Corporation, Woburn, MA 01801, USA.

We have observed that 8-4-[4-2-pyrimidyl)-1-piperazinyl]butyl]-8-azaspiro [4.5]decane-7.9-dione, an agent commonly known as buspirone HCl, possesses immunosuppressive activity when administered either topically or systemically, as assessed in a mouse model of contact hypersensitivity. Topical or systemic administration of buspirone significantly reduced the tissue swelling and leukocyte infiltration associated with the elicitation phase of contact hypersensitivity. Buspirone is a safe, widely used drug which has a history of use in humans throughout the world. These data demonstrate a previously unknown pharmacologic activity of buspirone.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=7613205&dopt=Abstract buspirone Buspar




J Pharmacol Exp Ther. 1996 Aug;278(2):898-905.
Novel benzodioxan derivative, 5-[3-[((2S)-1,4-benzodioxan-2-ylmethyl) amino]propoxy]-1,3-benzodioxole HCl (MKC-242), with anxiolytic-like and antidepressant-like effects in animal models.

Abe M, Tabata R, Saito K, Matsuda T, Baba A, Egawa M.

Pharmaceuticals Laboratory I, Yokohama Research Center, Mitsubishi Chemical Corporation, Japan.

Behavioral effects of MKC-242 (5- inverted question mark3-[((2>)-1,4-benzodioxan-2-ylmethyl)amino] propoxy inverted question mark-1,3-benzodioxole CHl), a novel and selective serotonin 1A receptor agonist, were investigated in rats and mice and compared against those of diazepam, buspirone and tandospirone. MKC-242 (0.0625-0.25 mg/kg, p.o.) significantly increased punished drinking in water-deprived rats. The reference compounds also increased punished drinking at doses of 10 to 40 mg/kg, p.o. The increase by MKC-242 was blocked by N-tert-butyl-3-(4-(2-methoxypenyl)piperazin-1-yl) -2-phenylpropanamide, a serotonin 1A receptor antagonist. MKC-242 (0.1-0.5 mg/kg, p.o.) also increased social interaction under high light and unfamiliar conditions in rats. It had weak benzodiazepine-like side effects in mice. MKC-242 (1, 3 mg/kg, p.o.) attenuated the reduction of locomotion caused by restraint stress in rats, the same effects were observed on both buspirone (100 mg/kg, p.o.) and tandospirone (100 mg/kg, p.o.). In the forced swimming test in rats, MKC-242 (0.3-3 mg/kg, i.p.), 8-hydroxy-2-(di-n-propylamino) tetralin (1, 3 mg/kg, i.p.) and amitriptyline (30 mg/kg, i.p.) reduced immobility, although diazepam, buspirone and tandospirone did not. The reduction by MKC-242 and 8-OH-DPAT was antagonized by N-tert-butyl-3-(4-(2-methoxyphenyl)piperazin-1-yl) -2-phenylpropanamide. Moreover, the reduction was also blocked by 1-(2--pyrimidinyl)piperazine (1-PP), a common metabolite of buspirone and tandospirone. These findings suggest that MKC-242 possesses potent anxiolytic and antidepressant properties that are mediated via an activa




Neuropeptides. 1996 Apr;30(2):187-92.
Different effects of the serotonergic agonists buspirone and sumatriptan on the posterior pituitary hormonal responses to hypoglycemia in humans.

Chiodera P, Volpi R, Capretti L, Caffarri G, Magotti MG, Coiro V.

Cattedra di Endocrinologia, Universita di Parma, Italy.

The responses of serum oxytocin (OT) and vasopressin (AVP) to the serotonergic HT1A agonist buspirone (15 mg p.o.) or the HTD1 agonist sumatriptan (6 mg injected subcutaneously) were evaluated in 7 normal men either in basal conditions or during an insulin (0.15 iu/kg as an i.v. bolus) tolerance test (ITT). Neither buspirone nor sumatriptan administration modified the basal secretion of AVP and OT. Stimulation of 5HT-1D receptors with sumatriptan was unable to change neither AVP nor OT response to insulin-induced hypoglycemia. On the other hand, the pretreatment with the 5HT1A agonist buspirone significantly enhanced the OT response during hypoglycemia, without modifying the AVP rise. The results of this study suggest that serotonergic 5HT1A receptors may interact with hypoglycemia in the stimulation of OT, but not AVP secretion.

http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&list_uids=8771561&dopt=Abstract buspirone Buspar




J Pharmacol Exp Ther. 1996 Mar;276(3):1111-27.
Comparison of the effects of typical and atypical anxiolytics on learning in monkeys and rats.

Winsauer PJ, Bixler MA, Mele PC.

Behavioral Sciences Department, Armed Forces Radiobiology Research Institute, Bethesda, Maryland, USA.

Atypical anxiolytics such buspirone have been reported to produce fewer disruptive effects on complex behaviors than some typical anxiolytics from the benzodiazepine class. To extend this analysis, several drugs from both drug classes were directly compared in two species (rhesus monkeys and rats) using a repeated-acquisition procedure. In monkeys responding under a multiple schedule of reinforcement consisting of acquisition (learning) and performance components, buspirone (0.032-0.52 mg/kg), 8-hydroxy-dipropylaminotetralin (8-OH-DPAT;0.032-0-56 mg/kg), chlordiazepoxide (CDZP; 1-56 mg/kg) and alprazolam (0.032-0.32 mg/kg) produced dose-dependent decreases in overall response rate in all subjects. However, with buspirone and 8-OH-DPAT, these rate-decreasing effects occurred in acquisition at lower doses than in performance. The effects on overall accuracy (i.e., percent errors) in monkeys were variable across drugs and drug classes. Both 8-OH-DPAT and alprazolam produced large increases in percent errors in acquisition at doses that had little or no effect on errors in performance. Buspirone also had differential effects on percent errors across components, but the error-increasing effects in acquisition were smaller. CDZP administered either orally or intramuscularly produced only small increases in errors, and these occurred at doses that substantially decreased the overall rate of responding in both components of the multiple schedule. In rats responding under a repeated-acquisition procedure, buspirone (1-5.6 mg/kg), 8-OH-DPAT (0.056-3.2 mg/kg) and CDZP (1.8-32 mg/kg) produced dose-dependent decreases in overall response rate. Similar to acquisition data in monkeys, buspirone and 8-OH-DPAT also increased percent errors t