Testicular Steroidogenesis in the Cebus Monkey throughout Postnatal Development1

Abstract

There is scant information on testicular steroidogenesis during postnatal development in monkeys, particularly in New World species. Our purpose was to study the in vitro steroidogenic capacity of the Cebus monkey testis from birth to advanced puberty. Fresh testicular tissue was incubated in Medium 199 with or without hCG (10 IU/ml); and levels of pregnenolone (P5), dehydroepiandrosterone (DHA), progesterone (P4), androstenedione (A), testosterone (T), dihydrotestosterone (DHT), and 3 alpha-androstanediol (3 alpha-DIOL) were measured in tissue and incubation media by RIA. To determine the predominant steroidogenic pathway, the ratio between the concentrations of the 5-ene and the 4-ene T precursors was determined, and the relative conversion of 3H-P5 and 14C-P4 to T was calculated. The number of Leydig cells per testis was determined in all experimental groups. The testes of the Cebus monkeys could produce T in vitro without the addition of gonadotropins at all ages. T and the 5-ene precursors (P5 and DHA) were the main steroids found within testicular tissue throughout postnatal development. T content per Leydig cell increased continuously with age, but testicular T concentration reached maximal levels at early puberty and did not change thereafter. The ratios between 5-ene and 4-ene T precursors ranged between 2.8 and 13.2, which suggested a predominance of the delta-5 pathway. This was confirmed by the finding that 3H-P5 was more efficiently converted to T than was 14C-P4. The T production relative to that of its d-ene precursors progressively increased to reach maximal values in late puberty.(ABSTRACT TRUNCATED AT 250 WORDS)

Augmented frequency and mass of LH discharged per burst are accompanied by marked disorderliness of LH secretion in adolescents with polycystic ovary syndrome

“…Serum concentrations of 17-OHP and testosterone were measured by commercial RIA kits (Diagnostics Products Corporation, Los Angeles, CA, USA and ICN Pharmaceuticals, Costa Mesa, CA, USA). Androstenedione was measured by RIA after ether extraction, as previously described by Rey et al (22). RIA of estradiol-17b and estrone was carried out using commercial kits (Diagnostics Products Corporation and Diagnostic Systems Laboratories Inc., Webster, TX, USA).…”

Facial Width-To-Height Ratio Relates to Alpha Status and Assertive Personality in Capuchin Monkeys

“…Additionally, theory concerning dominance cues in humans suggests a link between dominant behaviour and testosterone (e.g. [22]), with a pubertal spike in testosterone and consequent changes in morphology and behaviour [23], [24]. Such developmental changes may also occur for human fWHR given its association with adult levels of testosterone [25].…”

Hormonal correlates of male life history stages in wild white-faced capuchin monkeys (Cebus capucinus)

“…For example, Ginther et al (2002) found that the onset of puberty in cotton-top tamarins was marked by a significant rise in urinary DHT:T and remained elevated thereafter. In brown capuchin monkeys ( Sapajus [ Cebus ] apella ), metabolism of T into DHT in vitro testicular cells increased at the onset of puberty and continued into adulthood, though overall DHT levels were relatively low in comparison to other androgens (Rey et al, 1995). DHT production in maturing testicular cells and a subsequent increase in sexually mature individuals appears to be common among anthropoids and has been shown via in vitro analysis of testicular tissue in olive baboons ( Papio anubis ), rhesus macaques ( Macaca mulatta ), and orangutans ( Pongo pygmaeus ) (Preslock, 1980).…”