Interbular space characterization in adult capybara (Hydrochoerus hydrochaeris) testis

This study aimed at the qualitative and quantitative characterization of the different intertubular tissue components in adult male capybara. Testes of 15 adult capybaras from a commercial slaughterhouse of wild animals were used. The average percentage of Leydig cells was 32.95 ± 10.03 %, whereas in the other components of the intertubular space it was 14.95 ± 4.79 %, thus the whole intertubular space totalized 47.91 ± 11.48 %. The average weight of the testes were 32.83 ± 4.78g, while the animals' body weight were around 52.37 kg and the gonadosomatic and leydigosomatic indexes were 0.125 ± 0.02% and 0.0411 ± 0.0148% respectively. It was concluded that the leydigosomatic index of the capybaras was lower than the one observed in rats, as well as the arrangement of the components in intertubular tissue was similar to pattern I of Fawcett's classification as was found in guinea-pigs and chinchillas.Objetivou-se com esta pesquisa caracterizar qualitativamente e quantitativamente os diferentes componentes do tecido intertubular de capivaras machos adultas. Utilizou-se testículos de 15 capivaras adultas, provenientes de um abatedouro comercial de animais silvestres. Encontrou-se um percentual médio de células de Leydig de 32,95+10,03%, dos demais componentes do espaço intertubular de 14,95+4,79% e um total de espaço intertubular de 47,91+11,48%. O peso médio dos testículos foi de 32,83+4,78g, o peso corporal dos animais foi em torno de 52,37kg e os índices gonadossomático e leydigossomático foram, respectivamente, 0,125+0,02% e 0,0411+0,0148%. Concluiu-se que o índice leydigossomático das capivaras é menor que o observado em ratos e que o arranjo dos componentes do tecido intertubular é semelhante ao descrito como padrão tipo I da classificação de Fawcett, similar ao encontrado em cobaios e chinchilas

Interbular space characterization in adult capybara (Hydrochoerus hydrochaeris) testis

This study aimed at the qualitative and quantitative characterization of the different intertubular tissue components in adult male capybara. Testes of 15 adult capybaras from a commercial slaughterhouse of wild animals were used. The average percentage of Leydig cells was 32.95 ± 10.03 %, whereas in the other components of the intertubular space it was 14.95 ± 4.79 %, thus the whole intertubular space totalized 47.91 ± 11.48 %. The average weight of the testes were 32.83 ± 4.78g, while the animals' body weight were around 52.37 kg and the gonadosomatic and leydigosomatic indexes were 0.125 ± 0.02% and 0.0411 ± 0.0148% respectively. It was concluded that the leydigosomatic index of the capybaras was lower than the one observed in rats, as well as the arrangement of the components in intertubular tissue was similar to pattern I of Fawcett's classification as was found in guinea-pigs and chinchillas

Neonatal treatment with naloxone increases the population of Sertoli cells and sperm production in adult rats

Endogenous opioid peptides play an important role in the ontogenesis of the functional and morphological parameters of the seminiferous epithelium. The aim of this study was to evaluate the effects of neonatal manipulations with naloxone, an opioid antagonist, on the population of Sertoli cells and on sperm production in adult rats. Rats were assigned to receive 8 $\mu$g per gram of body weight twice a day with interval of 8 h of naloxone and they were compared to a control group receiving saline. Naloxone groups presented the following findings when compared to the control group: increased body weight from the 2nd to the 27th day; a smaller seminiferous epithelium height, smaller seminiferous tubule diameter, increased number of Sertoli cells and daily sperm production per testis, increased daily sperm production per gram per testis and increased total length of the seminiferous tubule of the treated groups. According to our study, the neonatal treatment with naloxone during the critical period of testis development was able to change the proliferative dynamics of Sertoli cells by an intra and/or extra testicular blockage of opioid receptors, confirming the direct relation between the number of Sertoli cells and the number of spermatozoids