In-vitro contractility of rat seminiferous tubules in response to prostaglandins, cyclic GMP, testosterone and 2,4'-dibromoacetophenone.

The effects of prostaglandin (PG) F-2 alpha and E-2, cyclic GMP, testosterone and 2,4'-dibromoacetophenone (DBA) on rat seminiferous tubules in vitro were ascertained by measuring contractile frequency, size of contractions and tone (tubular diameter). PGF-2 alpha (10(-9)--10(-5) M) increased frequency and tone but not magnitude of contraction. Contraction frequency and tone were decreased by PGE-2 (10(-9)--10(-5) M) but the size of contractions was again unaffected. Cyclic GMP (10(-10)--10(-6) M) increased the frequency of contractions and tone and decreased size of contractions. Testosterone decreased the frequency and size of contractions and increased tone at concentrations of 10(-9) to 10(-7) but higher concentrations (10(-6) M) reversed these changes. DBA (10(-7)--10(-3) M) greatly decreased the frequency and size of contractions and tone and spontaneous contractions were abolished at 10(-3) M. Our data strongly suggest that PGs, cyclic nucleotides and testosterone are all important in vivo in modulating contractility of seminiferous tubules and as such would participate in sperm transport from the testes.