Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Odorantes , Proteínas de Plantas/química , Sueño/efectos de los fármacos , Olfato/fisiología , Vigilia/efectos de los fármacos , Animales , Monoterpenos Bicíclicos , Masculino , Monoterpenos/química , Periodicidad , Ratas , Ratas Sprague-Dawley , Factores de TiempoRESUMEN
In mammals, circadian rhythms are driven by a pacemaker located in the suprachiasmatic nuclei (SCN) of the hypothalamus. The pacemaker is composed of an ensemble of multiple, single-cell oscillators in the SCN. We measured arginine-vasopressin (AVP) release in organotypic SCN slices. The SCN slice culture showed circadian oscillation of AVP release with a period length (+/- SEM) of 23.84 +/- 00.03 h. This period is very similar to the one we previously reported in dispersed SCN cultures and is also close to that of behavioural rhythms. When the ventral part was removed by a surgical cut across the slice in the horizontal plane, however, the period became shorter (23.22 +/- 00.08 h). On the other hand, the removal of the dorsal part did not affect period length. These results suggest that the oscillators in ventral and dorsal cells contribute differently to period length and that the dorsal oscillators are entrained by the ventral ones to form a single integrated oscillator.
Asunto(s)
Arginina Vasopresina/metabolismo , Ritmo Circadiano/fisiología , Núcleo Supraquiasmático/fisiología , Núcleos Talámicos Ventrales/fisiología , Animales , Animales Recién Nacidos , Técnicas In Vitro , Ratas , Ratas Sprague-Dawley , Núcleo Supraquiasmático/anatomía & histologíaRESUMEN
In our previous studies (Fujinoki et al., 2001, 2003), we reported that two types of 36 kDa proteins, designated 36K-A protein and 36K-B protein, obtained from hamster sperm flagella, are associated with motility activation and phosphorylated in a cAMP-dependent manner at serine residues. In the present experiments, we focused on the hamster (Mesocricetus auratus) 36K-A protein, which was analyzed by peptide mass finger printing and amino acid sequencing. The results suggest that 36K-A protein is a pyruvate dehydrogenase E1 component beta subunit lacking the N-terminal 30 amino acids. Moreover, our results suggest that 36 K-A protein is localized in the fibrous sheath of the principal piece of hamster spermatazoa.
Asunto(s)
Fosfoproteínas/aislamiento & purificación , Cola del Espermatozoide/química , Espermatozoides/química , Secuencia de Aminoácidos , Animales , Cricetinae , AMP Cíclico/metabolismo , Masculino , Datos de Secuencia Molecular , Peso Molecular , Péptidos/análisis , Péptidos/química , Fosfoproteínas/química , Fosforilación , Subunidades de Proteína/análisis , Subunidades de Proteína/química , Subunidades de Proteína/metabolismo , Piruvato Deshidrogenasa (Lipoamida)/metabolismo , Serina/química , Cola del Espermatozoide/enzimología , Cola del Espermatozoide/metabolismoRESUMEN
Background and Aims: Bromoacetic acids are a by-product of water ozonation and dibromoacetic acid (DBAA) in particular, which is a by-product of disinfection, inhibits male reproductive functions. In order to understand its effects, the spermatozoa and testes of mice were exposed to DBAA. Methods: Twelve-week-old ICR mice were exposed to 10 p.p.m. DBAA. They were examined in regards to effects on the weights of body, testis and epididymis, the histological changes of tesits and the protein expression in testis. Results: Neither the bodyweight nor the weights of the testis and epididymis of the exposed mice was affected, but approximately 13% of spermatozoa obtained from the cauda epididymis were motile with a drop-shaped head, and structures resembling residual bodies were found in the testis. Moreover, the expression of two testis proteins was changed by exposure to DBAA. Conclusions: It was likely that DBAA inhibited male reproductive functions by disturbance of spermatogenesis via change of protein expression. (Reprod Med Biol 2004; 3: 85-93).
RESUMEN
In our previous paper [M. Fujinoki et al. (2001) BIOMED: Res. 22, 45-58], we reported that the 58-kDa protein obtained from hamster sperm flagella was phosphorylated at serine residues in association with the start of motility. In the present experiments, we identified and localized the 58-kDa protein. The 58-kDa protein was assumed to exist in the acrosomal region domain of the sperm head and the whole sperm flagellum. In particular, a large amount of 58-kDa protein was localized in the equatorial segment of the acrosomal region domain of the sperm head and the middle piece of the sperm flagellum. In the next step, the 58-kDa protein was identified by peptide mass finger printing and LC-MS/MS analysis. The results suggested that the 58-kDa protein was ATP synthase H(+) transporting F1 beta, which is one of the mitochondrial components. Therefore, it is likely that the 58-kDa protein is associated with ATP production in the mitochondrial sheath in the middle piece of the sperm flagellum, and H(+) transport in the sperm head and the sperm flagellum except for the middle piece, since ATP synthase also acts as an H(+) pump.
Asunto(s)
Fosfoproteínas/química , Fosfoproteínas/fisiología , Motilidad Espermática , Espermatozoides/metabolismo , Secuencia de Aminoácidos , Animales , Membrana Celular/metabolismo , Cricetinae , Electroforesis en Gel Bidimensional , Electroforesis en Gel de Poliacrilamida , Inmunohistoquímica , Masculino , Espectrometría de Masas , Mitocondrias/metabolismo , Datos de Secuencia Molecular , Péptidos/química , Fosforilación , ATPasas de Translocación de Protón/química , Cola del Espermatozoide/metabolismoRESUMEN
In our previous paper [M. Fujinoki et al. (2001) BIOMED: Res. 22, 45-58], we reported that two types of 36-kDa protein, which were designated as 36K-A protein and 36K-B protein, obtained from hamster sperm flagella were phosphorylated at serine residues associated with the regulation of motility activation. In the present experiments, it was suggested that these two types of 36-kDa protein were phosphorylated in a cAMP-dependent manner associated with motility activation of hamster spermatozoa. Because the 36K-B protein was the most intensely phosphorylated in a cAMP-dependent manner, attempts were made to further characterize it. The 36K-B protein was assumed to be localized in the middle piece. The localization of the 36K-B protein was the same as that of the 36-kDa protein reported in our previous paper [Y. Si et al. (1999) Mol. Reprod. Dev. 52, 328-334]. In order to identify the 36K-B protein, it was analyzed by peptide mass finger printing and amino acid sequencing. The results suggested that the 36K-B protein was a pyruvate dehydrogenase E1 component beta subunit and a component of the mitochondrial sheath of the middle piece.