title: Endocannabinoid system in frog and rodent testis: type-1 cannabinoid receptor and fatty acid amide hydrolase activity in male germ cells.
abstract: N-arachidonoylethanolamide (anandamide [AEA]) is the main endocannabinoid described to date in the testis. It exerts its effects through the activation of G-protein coupled cannabinoid receptors (CNR). However, the activity of AEA in controlling male reproduction is still poorly known. Here we provide direct evidence on the presence of the "endocannabinoid system," constituted by type-1 cannabinoid receptor (CNR1) and fatty acid amide hydrolase (FAAH), in the frog Rana esculenta testis demonstrating its expression in tubular compartment. In fact, during the annual reproductive cycle, both proteins increase in September, when the appearance of spermatids (SPT) occurs. Immunocytochemistry confirms their localization in germ cells and, in particular, in elongated SPT. Signals are still present in spermatozoa (SPZ), as demonstrated by Western blot analysis. Furthermore, the activation of CNR1 reduces sperm motility. Comparative research, carried out using mouse and rat SPZ, definitely indicates that the endocannabinoid system operates in SPZ of phylogenetically distant species. A conserved physiological role of endocannabinoid system in controlling the inhibition of sperm motility is suggested.
authors.affiliation: Dipartimento di Medicina Sperimentale, Sez. F. Bottazzi, II Università di Napoli, 80138 Napoli, Italy.
authors.forename: Gilda
authors.initials: G
authors.lastname: Cobellis
authors.forename: Giovanna
authors.initials: G
authors.lastname: Cacciola
authors.forename: Donatella
authors.initials: D
authors.lastname: Scarpa
authors.forename: Rosaria
authors.initials: R
authors.lastname: Meccariello
authors.forename: Rosanna
authors.initials: R
authors.lastname: Chianese
authors.forename: Maria Fosca
authors.initials: MF
authors.lastname: Franzoni
authors.forename: Ken
authors.initials: K
authors.lastname: Mackie
authors.forename: Riccardo
authors.initials: R
authors.lastname: Pierantoni
authors.forename: Silvia
authors.initials: S
authors.lastname: Fasano
mesh_terms: D000581:Amidohydrolases / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D000818:Animals; D001095:Arachidonic Acids / Q000494:pharmacology; D005075:Biological Evolution; D063385:Cannabinoid Receptor Modulators / Q000378:metabolism*; D063388:Endocannabinoids; D004791:Enzyme Inhibitors / Q000494:pharmacology; D008297:Male; D051379:Mice; D053284:Polyunsaturated Alkamides; D011893:Rana esculenta; D051381:Rats; D017207:Rats, Sprague-Dawley; D043882:Receptors, Cannabinoid / Q000235:genetics / Q000378:metabolism*; D013094:Spermatozoa / Q000187:drug effects / Q000201:enzymology / Q000378:metabolism*; D013737:Testis / Q000378:metabolism; D000099252:Fatty Acid Amide Hydrolases
chemical_list: D000581:Amidohydrolases; D001095:Arachidonic Acids; D063385:Cannabinoid Receptor Modulators; D063388:Endocannabinoids; D004791:Enzyme Inhibitors; D053284:Polyunsaturated Alkamides; D043882:Receptors, Cannabinoid; D000099252:Fatty Acid Amide Hydrolases; C078814:anandamide; C107594:N-(4-hydroxyphenyl)arachidonylamide