副睾丸に関する研究 第2報 : 家兎副睾丸組織中カルニチン濃度について

Abstract

家兎副睾丸, 精管および睾丸の組織中カルニチン濃度を前橋らの酵素法で測定し, 実験的に急性副睾丸炎と精管結紮を施行した時のカルニチン濃度を検討した.コントロール群の濃度はproximal caudaが最高値(1378.9±663.0 μg/g wet wt)を示し, ついでdistal cauda, ductus deferns, corpus, caput, testisの順であった.副睾丸尾部カルニチン濃度が全体の73%を占めた.急性副睾丸炎群のカルニチン濃度はcaputが最高値221.9±209.3 μg/g wet wtで他の部位はcaputのほぼ1/3位の値を示した.コントロール群に比しcorpus, proximal cauda, distal caudaは有意な濃度低下を示し, またductus deferensも減少していた.精管結紮1週と1ヵ月後の組織内濃度はコントロール群に比し, caput, corpus, caudaで増加し, 2ヵ月と3ヵ月の濃度は全般的に減少傾向を示したが, 統計学的有意差を認めなかった.以上の成績より, 副睾丸組織中のカルニチン濃度を測定することにより副睾丸の機能を推測することが可能であることが判った

Carnitine is known to be indispensable to β-oxidation of long-chain fatty acids and it occurs in seminal fluid, spermatozoa, and epididymis tissue. In the present study, epididymal tissue levels of carnitine were measured based on the assumption that such measurement would provide an insight into epididymal secretory function. Materials and Methods: Male rabbits each weighing about 3 kg were used. Experimental acute epididymitis was induced by inoculating into the vas deferens 0.1 ml of Ps. aeruginosa A14, inoculum size adjusted to 10[5] cells/ml, and the animals were examined 4 days after surgery. For the vasectomy group, only the vas deferens was ligated, and animals in this group were studied at 1 week and 1, 2 and 3 months after surgery. Epididydal tissue levels of carnitine were determined by the enzymatic method of Maebashi et al. Results: The mean tissue level of carnitine in the control group (12 rabbits) was 350.7± 136.5 µg/g wet wt for the epididymal caput, 573.5±282.l µg/g wet wt for the corpus, 1, 378.9± 663.0 pg/g wet wt for the proximal cauda, 1, 134.9±475.3 pg/g wet wt for the distal cauda, 723.5 ±459.2 pg/g wet wt for the vas deferens, and 199.4±232.9 pg/g wet wt for the testicle. In the acute epididymitis group (6 rabbits), on the other hand, epididymal tissue levels of carnitine were remarkably lower than that in the control (t<0.001), with the mean tissue level of carnitine in these diseased animals being 159.0± 119.1 µg/g wet wt for the corpus, 76.1 ±48.8 µg/g wet wt for the proximal cauda, and 60.0±46.9 µg/g wet wt for the distal cauda. Even in the vas deferens it was significantly lowered to 140.8±127.3 pg/g wet wt (t<0.01). In the vasectomy group (3 rabbits), the tissue levels of carnitine in the epididymal caput, corpus and cauda showed a tendency toward elevation at 1 week and 1 month after surgery. At 2 and 3 months, the epididymal tissue levels of carnitine in this group were generally lowered, but the difference in level compared to that of the control was not statistically significant.