The role of the genitofemoral nerve and calcitonin gene-related peptide in congenitally cryptorchid mutant TS rats.
We investigated whether previous gubernacular denervation in TS rats changes the gubernacular contractile response to or binding capacity of calcitonin gene-related peptide receptors. In TS rats there is excessive calcitonin gene-related peptide in the genitofemoral nerve and 85% of the male rats have cryptorchidism. TS rats and controls underwent genitofemoral nerve transection or sham operation at day 0. On day 3 gubernacula were cultured with or without calcitonin gene-related peptide to observe contractions. Gubernacular frozen sections were incubated with 125iodine calcitonin gene-related peptide with or without unlabeled calcitonin gene-related peptide. Exposed x-ray films were quantified by computerized densitometry. In the sham operated controls contractility increased from 15 to 55% by adding calcitonin gene-related peptide compared with 5% and 10%, respectively, in the TS rats. After genitofemoral nerve denervation exogenous calcitonin gene-related peptide increased contractility to 90% in controls and 75% in TS rats. Previous genitofemoral nerve transection increased specific 125iodine calcitonin gene-related peptide binding 21% in controls and about 100% in TS rats. Genitofemoral nerve transection in TS rats restored gubernacular contractile response to calcitonin gene-related peptide in vitro and doubled the binding capacity of calcitonin gene-related peptide receptors.
Terada
M
M
Department of General Surgery, Royal Children's Hospital, Melbourne, Australia.
Hutson
J M
JM
Farmer
P J
PJ
Goh
D W
DW
D000818:Animals; D003456:Cryptorchidism / Q000503:physiopathology*; D003714:Denervation; D005837:Genitalia, Male / Q000294:innervation* / Q000502:physiology; D008297:Male; D011485:Protein Binding; D051381:Rats; D011922:Rats, Mutant Strains; D017207:Rats, Sprague-Dawley; D018015:Receptors, Calcitonin Gene-Related Peptide / Q000502:physiology*
D018015:Receptors, Calcitonin Gene-Related Peptide