Neocuproine, a copper (I) chelator, potentiates purinergic component of vas deferens contractions elicited by electrical field stimulation.
Effects of the specific copper (I) chelator, neocuproine, on the purinergic and adrenergic components of nerve-evoked contractions were investigated in the prostatic rat vas deferens. Electrical field stimulation (EFS; 4 Hz) induced bimodal contractions of vas deferens tissue in the presence of alpha1-adrenoceptor antagonist prazosin (to isolate the purinergic component) or purinoceptor antagonist suramin (to isolate the adrenergic component). Neocuproine significantly potentiated the purinergic component of the contractile responses to EFS. However, the same agent failed to elicit any significant effect on the adrenergic component of nerve-evoked contractions. The copper (II) chelator cuprizone could not affect the purinergic component of contractions. The potentiating effect of neocuproine which was reversible after washout of the drug, did not occur following the application of the pre-prepared neocuproine-copper (I) complex. A nitric oxide synthase inhibitor, L-nitroarginine; a cyclooxygenase inhibitor, indomethacin or an alpha2-adrenoceptor antagonist, yohimbine, failed to alter the responses to neocuproine on the purinergic component of the contraction to EFS. Neocuproine did not elicit any significant effect on preparations in which the purinergic receptors were desensitized with alpha,beta-methylene ATP. In conclusion, our results suggest that neocuproine potentiates the purinergic component of rat vas deferens contractions elicited by EFS, presumably by facilitating purinergic neurotransmission and that copper (I)-sensitive mechanisms can modulate purinergic transmission in this tissue.
Göçmen
Cemil
C
Department of Pharmacology, School of Medicine, University of Cukurova, Adana, Turkey. cgocmen@mail.cu.edu.tr
Kumcu
Eda Karabal
EK
Büyüknacar
H Sinem
HS
Onder
Serpil
S
Singirik
Ergin
E
D000255:Adenosine Triphosphate / Q000031:analogs & derivatives / Q000494:pharmacology; D000818:Animals; D002614:Chelating Agents / Q000494:pharmacology*; D004558:Electric Stimulation; D066298:In Vitro Techniques; D008297:Male; D009119:Muscle Contraction / Q000187:drug effects*; D009569:Nitric Oxide / Q000502:physiology; D010618:Phenanthrolines / Q000494:pharmacology*; D011224:Prazosin / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D011983:Receptors, Purinergic / Q000502:physiology*; D013498:Suramin / Q000494:pharmacology; D014649:Vas Deferens / Q000187:drug effects* / Q000502:physiology
D002614:Chelating Agents; D010618:Phenanthrolines; D011983:Receptors, Purinergic; D009569:Nitric Oxide; D013498:Suramin; C002701:neocuproine; D000255:Adenosine Triphosphate; C002630:alpha,beta-methyleneadenosine 5'-triphosphate; D011224:Prazosin