Improved sexual behavior in male rats treated with a Chinese herbal extract: hormonal and neuronal implications.
OBJECTIVE
To investigate the influence of an extract obtained from five Chinese medicinal plants on sexual behavior of adult male rats.


METHODS
The extract was administered at doses of 30, 60 and 120 mg/kg by oral gavage, acutely (one time, 45 min before mating test) or subchronically (daily for 10 days) in sexually potent and sexually sluggish/impotent rats. Sexual behavior, serum levels of luteinizing hormone (LH) and testosterone (T) were evaluated in treated rats and compared with controls receiving vehicle. The effect of the extract on central dopaminergic neurotransmission was assessed in the nucleus accumbens using a microdialysis technique.


RESULTS
In sexually potent rats, both acute and subchronic treatment with the extract dosed at 30 and 60 mg/kg reduced mount latency and intromission latency. In sluggish/impotent rats, the acutely administered extract at the dose of 60 mg/kg shortened ejaculation latency, whereas subchronically administered at the doses of 30 and 60 mg/kg, reduced mount, intromission and ejaculation latencies, increasing also the percentage of mounting and ejaculating rats. The extract dosed at 60 mg/kg significantly increased LH and T following acute and subchronic administration and increased 3,4-dihydroxyphenylacetic acid levels in the nucleus accumbens, 30 min after the acute administration.


CONCLUSIONS
The improvement in both appetitive and consummatory components of sexual behavior observed in male rats treated with the extract could be ascribed to increased serum T level in parallel with the activation of the central dopaminergic system.
Zanoli
Paola
P
Department of Biomedical Sciences, University of Modena and Reggio Emilia, Via G. Campi 287, Modena 41100, Italy. zanoli.paola@unimore.it
Benelli
Augusta
A
Zavatti
Manuela
M
Rivasi
Marianna
M
Baraldi
Claudia
C
Baraldi
Mario
M
D000818:Animals; D001923:Brain Chemistry / Q000187:drug effects; D002490:Central Nervous System / Q000187:drug effects*; D003307:Copulation / Q000187:drug effects; D004298:Dopamine / Q000502:physiology; D004365:Drugs, Chinese Herbal / Q000494:pharmacology*; D004542:Ejaculation / Q000187:drug effects; D007172:Erectile Dysfunction / Q000188:drug therapy / Q000523:psychology; D005260:Female; D012739:Gonadal Steroid Hormones / Q000097:blood*; D007986:Luteinizing Hormone / Q000097:blood; D008297:Male; D017551:Microdialysis; D009042:Motivation; D010936:Plant Extracts / Q000494:pharmacology; D010946:Plants, Medicinal / Q000737:chemistry; D051381:Rats; D017207:Rats, Sprague-Dawley; D012726:Sexual Behavior, Animal / Q000187:drug effects*; D013268:Stimulation, Chemical; D009435:Synaptic Transmission / Q000187:drug effects; D013739:Testosterone / Q000097:blood
D004365:Drugs, Chinese Herbal; D012739:Gonadal Steroid Hormones; D010936:Plant Extracts; D013739:Testosterone; D007986:Luteinizing Hormone; D004298:Dopamine