Insulin receptor substrate-I (IRS-I) is a major cytosolic substrate of the insulin receptor Expression of insulin receptor and IRS-I, and the distribution of these components of the insulin-signalling pathway, were investigated in rat retinae. Insulin receptor and IRS-I were located in retinal sections with anti-insulin receptor and anti-IRS-I antibodies. Reverse transcription-polymerase chain reaction (RT-PCR) of retinal mRNA was performed with primers specific for insulin receptor and IRS-I gene sequences. Immunohistochemistry demonstrated distinct but closely associated staining patterns for insulin receptor and IRS-I throughout rat retinae. The RT-PCR product from rat retinal insulin receptor mRNA corresponded to the high affinity insulin receptor isoform. The RT-PCR product for retinal IRS-I mRNA agreed with that predicted from the gene sequence. The expression of IRS- I and insulin receptors indicates a signalling mechanism by which insulin can influence retinal metabolism or function.

Background Feline immunodeficiency virus (FIV) and human immunodeficiency virus (HIV) infection cause similar clinical syndromes of immune dysregulation, opportunistic infections, inflammatory diseases, and neoplasia. Renal disease is the 4th most common cause of death associated with HIV infection. Objective To investigate the association between FIV infection and renal disease in cats. Animals Client‐owned cats (153 FIV‐infected, 306 FIV‐noninfected) and specific‐pathogen‐free (SPF) research colony cats (95 FIV‐infected, 98 FIV‐noninfected). Methods A mixed retrospective/prospective cross‐sectional study. Blood urea nitrogen (BUN), serum creatinine, urine specific gravity (USG), and urine protein:creatinine ratio (UPC) data were compared between FIV‐infected and FIV‐noninfected cats. In FIV‐infected cats, total CD4+ and CD8+ T lymphocytes were measured using flow cytometry, and CD4+:CD8+ T lymphocyte ratio was calculated. Renal azotemia was defined as a serum creatinine ≥ 1.9 mg/dL with USG ≤ 1.035. Proteinuria was defined as a UPC > 0.4 with an inactive urine sediment. Results Among the client‐owned cats, no association was detected between FIV infection and renal azotemia (P = .24); however, a greater proportion of FIV‐infected cats were proteinuric (25.0%, 16 of 64 cats) compared to FIV‐noninfected cats (10.3%, 20 of 195 cats) (P < .01). Neither neuter status nor health status were risk factors for proteinuria in FIV‐infected cats, but UPC was positively correlated with the CD4+:CD8+ T lymphocyte ratio (Spearman's rho = 0.37, P = .01). Among the SPF research colony cats, no association was detected between FIV infection and renal azotemia (P = .21) or proteinuria (P = .25). Conclusions and Clinical Importance Proteinuria but not azotemia was associated with natural FIV infection.

SummaryT he objective of this study was to establi sh an effective post-operati ve analgesic regim en for Sprague-Dawley (SD ) and Dark Agouti (DA) rats. Buprenorphine (0.01 or 0.05 mg=kg), a partial m opioid agonist, was administered subcutaneously immediately on completion of a standardized surgical procedure, involving anaesthesia, laparotom y and visceral manipulation. Two of the four treatm ent groups and the saline control group received a second injection 9 h later. Behavioural observations by three independent observers provided no information in assessing pain in this model. All rats lost weight, consumed less food and water after surgery. On the ®rst day, both SD and DA rats receiving buprenorphine lost less weight than untreated control groups. Using weight loss as an ef®cacy criterion, low-dose buprenorphine, given once or twice, provided effective analgesia in SD rats. A higher single dose provided no additional bene®t and a second dose was detrimental, reducing body weight and food intake. In DA rats, the high dose, given twice, appeared to be more effective than the lower dose. All DA cage cohorts consumed <10 % pre-operative food despite buprenorphine treatm ent, suggesting a higher dosage may be necessary. However, all SD and 80 % DA rats who received no buprenorphine gained body weight on the second day, whereas most of the buprenorphine-treated rat s continued to lose weight for another 2 days, despite increased food consumption by both strains. Buprenorphine may adversely affec t intestinal function over a number of days due to its enterohepatic circulation; this effect may be more severe in DA rats. Adverse metabolic effects of buprenorphine and other opioids may preclude their use in the future if it can be shown that non-steroidal anti-in¯am matory drugs (NSAIDs) provide equally effective analgesia.

Celsior was not as effective as MUW for rat heart preservation. The addition of NTG to both CEL and MUW provided similar effective preservation for 16 hr. NTG should be added routinely to both solutions.