Developmental expression of p97/VCP (Valosin-containing protein) and Jab1/CSN5 in the rat testis and epididymis.

BACKGROUND: The ubiquitin proteasome system (UPS) is a key player in regulating many cellular processes via proteasomal degradation of ubiquitinated proteins. Recently published data show that Jab1/CSN5 interacts with p97/VCP and controls the ubiquitination status of proteins bound to p97/VCP in mouse and human cells. However, coexpression of p97/VCP and Jab1/CSN5 in the developing rat testis and epididymis has not previously been studied. METHODS: Testicular and epididymal tissues from 5-, 15-, 30-, and 60-day-old rats were examined by immunohistochemistry and Western blotting. Colocalisation of proteins was determined by immunofluorescence microscopy. RESULTS: In the 5-day-old rat testis, p97/VCP and Jab1/CSN5 were specifically expressed in gonocytes. The expression of p97/VCP and Jab1/CSN5 significantly increased at day 15 and was found in spermatogonia, Sertoli cells and spermatocytes. In 30- and 60-day-old rat testes, p97/VCP indicated moderate to strong expression in Sertoli cells, spermatogonia, round and elongating spermatids. However, moderate to weak expression was observed in spermatocytes. Jab1/CSN5 showed strong expression in spermatogonia and spermatocytes, while relatively moderate expression was observed in round and elongating spermatids in 30- and 60-day-old rat testes. In contrast, in the epididymis, the expression of both proteins gradually increased from 5 to 60 days of age. After rats reached 2 weeks of age, the expression of both proteins was mostly restricted to the basal and principal cells of the caput epididymis. CONCLUSIONS: Our study suggests that p97/VCP and Jab1/CSN5 could be an important part of the UPS in the developing rat testis and epididymis and that both proteins may be involved in the regulation of spermatogenesis and epididymal epithelial functions.

A novel antibiotic, linezolid, reduces intraperitoneal adhesion formation in the rat uterine horn model.

OBJECTIVE: To examine the effects of linezolid in prevention of adhesion formation in a rat uterine horn model. DESIGN: Prospective randomized study. SETTING: University Experimental Animal Research Laboratory Center. SAMPLE: Ninety female Wistar albino rats. METHODS: A dose response study was first conducted with 60 Wistar albino rats that were randomly assigned to six equal groups by administering vehicle (control), 5 mg/kg (Group 1), 15 mg/kg (Group 2), 50 mg/kg (Group 3), 100 mg/kg (Group 4), and 150 mg/kg (Group 5) linezolid starting three days before the adhesion inducing operation and continuing for 14 days postoperatively. Adhesion was scored clinically with a scoring system. The minimum effective dose was found to be 100 mg/kg/day. With this dose time response (starting three days before the operation and continuing for seven days), only preoperative and postoperative administration studies were conducted. MAIN OUTCOME MEASURES: Extent and severity of adhesions. RESULTS: Total adhesion scores in the control and Groups 1 and 2 were significantly higher when compared with Groups 4 and 5, but not with Group 3. There were no significant differences in the adhesion scores between Groups 3, 4, and 5. In time response arm a total of 10 days treatment was not as effective as 17 days treatment. In postoperative and preoperative arms of the study, it was found that administration of linezolid only postoperatively or preoperatively did not affect adhesion formation significantly when compared with the control group. CONCLUSION: Linezolid was found to reduce intraperitoneal adhesion formation.

Interaction between Smad1 and p97/VCP in rat testis and epididymis during the postnatal development.

Members of the bone morphogenetic proteins (BMPs) superfamily are expressed in the testis and epididymis and are believed to have different biological functions during testicular and epididymal development. Smad1 is one of the signal transducers of BMP signaling and binds to several proteins involved in ubiquitin-proteasome system (UPS). Valosin-containing protein (p97/VCP) is required for the degradation of some UPS substrates. Although p97/VCP has been indicated in different cellular pathways, its association with BMP signaling in male reproductive system has not been elucidated. The aim of the present study was to investigate the cellular localization of Smad1, phospho-Smad1, and p97/VCP and the interaction of proteins in the postnatal rat testis and epididymis. Testicular and epididymal tissues from 5-, 15- and 60-day-old rats were examined by immunohistochemistry, immunofluorescence, Western blotting, and immunoprecipitation techniques. In 5-day-old rat testis, Smad1, phospho-Smad1, and p97/VCP were mainly expressed in gonocytes. In 15- and 60-day-old rat testis, proteins were overlapped in spermatogonia, Sertoli cells, and spermatocytes. Expression of proteins in the epithelial cells of epididymis was gradually increased from 5 to 15 days of age. Smad1 and phospho-Smad1 expressions showed uniformity in the different regions of epididymis, however p97/VCP immunoreactivity was higher only in caput epididymis compared to corpus and cauda epididymis in 15- and 60-day-old rat epididymis. Co-immunoprecipitation experiments further confirmed the Smad1-p97/VCP and p-Smad1-p97/VCP interactions. The overlap between Smad1 and p97/VCP expressions in the postnatal rat testis and epididymis suggests that p97/VCP may play important roles in mediating BMP signaling during spermatogenesis.

Comparison of ketamine-diazepam with ketamine-xylazine anesthetic combinations in sheep spontaneously breathing and undergoing maxillofacial surgery.

The objective of this study was to choose a suitable anesthetic combination for use in experimental surgical models by comparing the anesthetic and cardio-respiratory changes. Fourteen healthy male sheep were randomly assigned to two different drug regimens. In Group 1 the sheep were anesthetized with ketamine + xylazine (22 mg/kg im. + 0.2 mg/kg i.m., respectively). Anesthetic combination of ketamine + diazepam (22 mg/kg im. + 0.4 mg/kg i.m., respectively) was used in Group 2. Heart rate, respiratory rate and mean arterial pressures were evaluated before anesthesia, after induction of anesthesia up to 30 minutes in 5 minute intervals and during recovery. In all sheep, duration of anesthesia induction, duration of anesthesia and duration of recovery were recorded. Quality of induction, anesthesia, analgesia and recovery were evaluated. Cardio-respiratory parameters decreased below baseline values after anesthesia induction in both groups. However, no profound effects on cardio-respiratory functions were observed during study. In Group 2, it was observed that; anesthesia induction time was longer, the depth of anesthesia was inadequate during the osteotomy stage of the surgical procedure and recovery time was longer in comparison to Group 1. Otherwise the quality of anesthesia induction, anesthesia, analgesia and recovery was better in Group 1 than Group 2. These findings indicate that both drug combinations can provide short time anesthesia for minor surgical procedures. Ketamine+xylazine combination can be used as a more suitable anesthetic combination in experimental surgical procedures such as maxillofacial surgery than ketamine+diazepam combination, in sheep.