[Changes in circulation during extradural spinal anesthesia].

In parotid glands of pentobarbitone-anaesthetized rats, the incorporation of [3H]leucine into trichloroacetic acid-insoluble materials, reflecting protein synthesis, increased by 17% (compared to saline-treated rats) in response to infusion of pentagastrin (20 microg kg(-1), i.v. for 1 h) under muscarinic and alpha- and beta-adrenoceptor blockade. Both the CCK-A receptor antagonist lorglumide (48 mg kg(-1), i.v.) and the CCK-B receptor antagonist itriglumide (5.5 mg kg(-1), i.v.), given separately, prevented the expected increase in pentagastrin and, in addition, reduced the glandular protein synthesis by 16 and 12%, respectively, below the level of saline-treated rats. In rats treated with saline only, the glandular protein synthesis was reduced by 22% by the CCK-A receptor antagonist and by 17% by the CCK-B receptor antagonist; combined, the two antagonists caused no further reduction (20%). There was no increase in the glandular protein synthesis of pentagastrin-treated rats compared to that of the saline-treated rats when both groups of rats were exposed to a combination of the two types of CCK receptor antagonists. In pentagastrin-treated rats, the protein synthesis in the parotid glands was 23% less in the presence of the non-selective nitric oxide (NO) synthase inhibitor L-NAME (30 mg kg(-1), i.v.) than in its absence; the result was the same (23%) when the neuronal NO synthase inhibitor Nomega-propyl-L-arginine (N-PLA; 30 mg kg(-1), i.v.) replaced L-NAME. The protein synthesis in rats treated with saline only was not reduced by L-NAME; nor was the protein synthesis of saline-treated rats different from that of pentagastrin- and L-NAME-treated rats. Thus, under 'basal' conditions, a portion of the glandular protein synthesis, as well as the whole increase in synthesis in response to administration of pentagastrin, engaged both types of CCK receptors. Furthermore, NO generation, owing to neuronal NO synthase activity, was required for the increase to occur in response to pentagastrin, whereas a non-NO-dependent pathway was responsible for the protein synthesis under 'basal' conditions.

Anesthesia↗

PubMed2006

The use of propofol for electroejaculation in domestic cats.

The objective was to evaluate the use of propofol as an anesthetic drug for electroejaculation in the domestic cat. Cortisol concentrations, heart rates and respiratory rates of 20 male domestic cats were examined. The animals were randomly allocated into three groups. Group A (n = 8), were anesthetized with propofol (10 mg/kg) and underwent electroejaculation. Group B (n = 6), were pre-medicated with buprenorphine (0.01 mg/kg), anesthetized with propofol (5 mg/kg) and underwent electroejaculation. Group C (n = 6), the cats were anesthetized with propofol (10 mg/kg) without electroejaculation (control group). Blood samples were collected at four time points (30 min before propofol administration, immediately after the surgical plane of anesthesia was induced, immediately post-electroejaculation, and at the onset of anesthetic recovery). In the control group, the sampling time coincident with the end of electroejaculation was assigned as 21 min after the induction of anesthesia. The mean (+/- S.E.M.) duration time for electroejaculation was 18 +/- 3 min. The duration of anesthesia did not differ (P > 0.05) among the three groups of cats (26 +/- 2 min). Most of the cats (17/20) recovered smoothly. Pre-anesthetic medication with buprenorphine did not reduce the requirement of propofol for anesthesia. The cortisol concentrations, heart rates and respiratory rates of the three groups of cats did not differ (P > 0.05). A marked decline in cortisol levels was observed immediately post-electroejaculation. Propofol was a useful anesthetic for electroejaculation in felids with rapid onset, optimal duration of anesthesia for performing electroejaculation, and smooth recovery.

Anesthesia↗