Mechanisms involved in contractile differences among cremaster muscles according to localization of testis

• Published in: Journal of pediatric surgery 2001-10, Vol.36 (10), p.1551-1560
• Main Authors: Tanyel, F.Cahit, Ertunç, Mert, Büyükpamukçu, Nebil, Onur, Rüştü
• Format: Article
• Language: English
• Subjects: Adult; autonomic nervous system; Biological and medical sciences; calcitoin gene-related peptide; calcium channels; Cranial nerves. Spinal roots. Peripheral nerves. Autonomic nervous system. Gustation. Olfaction; Cremaster muscle; cryptorchidism; Cryptorchidism - physiopathology; Gynecology. Andrology. Obstetrics; Hernia, Inguinal - physiopathology; Humans; inguinal hernia; Isoproterenol - pharmacology; Male; Male genital diseases; Medical sciences; Middle Aged; Muscle Contraction; Muscle, Smooth - physiology; Nervous system (semeiology, syndromes); Neurology; Non tumoral diseases; substance P; Testis - physiology; Verapamil - pharmacology
• ISSN: 0022-3468; 1531-5037
• DOI: 10.1053/jpsu.2001.27042

Background/Purpose: Evidence suggests differences in contractility in cremaster muscles (CM) associated with undescended testis caused by alterations of autonomic innervation. Contractile responses of CM to various pharmacologic agents were evaluated and compared according to the localization of testis. Methods: Samples of CM from boys with undescended testis or inguinal hernia were obtained. Twitch and tetanic contractions were recorded isometrically at 37°C. Effects of verapamil, isoprenaline, calcitonin gene-related peptide (CGRP), substance P (SP) and Nω-nitro-L-arginine (L-NNA) were investigated. Results were compared through 2-way analysis of variance, and P values less than .05 were considered to be different. Results: Verapamil alone significantly (P < .05) decreased contraction amplitudes in CM from both sources; the decrease was more pronounced in CM from boys with inguinal hernia (P < .05). Although isoprenaline increased contraction amplitudes in CM associated with undescended testis (P < .05), CGRP and SP increased contraction amplitudes in CM associated with descended testis (P < .05). L-NNA increased contraction amplitudes in both groups (P < .05). The decrease of contraction amplitudes after verapamil displayed a similar pattern after isoprenaline, SP, and L-NNA. Verapamil-induced contractility decrease was more pronounced after CGRP in both groups (P < .05). Conclusions: Sensitivity of CM to verapamil differs according to localization of testis. Isoprenaline enhances contractility by stimulating Na+-K+ATPase in undescended testis without altering voltage-sensitive channel sensitivity to verapamil. CGRP and SP increase contractility in inguinal hernia, and CGRP increases the sensitivity of voltage-sensitive Ca2+ channels to verapamil in CM from both groups. Nitric Oxide (NO) exerts inhibitory action on CM contractility, and it is less pronounced in undescended testis. These differences may contribute to pathophysiology of undescended testis. J Pediatr Surg 36:1551-1560. Copyright © 2001 by W.B. Saunders Company.