Naloxone reversal of hemorrhagic hypotension in the conscious guinea-pig is impeded by inhibition of the renin-angiotensin II system.

Naloxone reverses hemorrhagic hypotension in the conscious guinea-pig. Captopril and saralasin impede this naloxone effect, suggesting that angiotensin II is involved in naloxone action. This is compatible with previous work which has shown that B-endorphin inhibits the centrally mediated pressor action of angiotensin II, and that naloxone blocks this effect. Naloxone may be interacting with the postulated brain renin-angiotension II system or may be blocking the action of shock-induced circulating angiotensin II on a centrally located area such as the hypothalamus.

Evaluation of the Beckman Synchron CX4 clinical chemistry analyzer in a hospital laboratory.

The Beckman Synchron CX4 random-access multianalyzer was evaluated in a medium sized hospital laboratory. The instrument does end-point, rate, and multipoint assays and carries on-board reagents for 24 tests. In addition to predefined tests, the instrument can be programmed for 100 user-defined tests; these are stored on the hard disk and can utilize up to three component reagents each. The throughput is 200 tests per hour. There is stat testing capability. In our evaluation, within-run and between-run precision and linearity were good, and no reagent carryover was detected. There was good correlation with the in-house methodology for the 19 tests evaluated. A disadvantage at the time of evaluation was interference by elevated bilirubin on creatinine, phosphorus, uric acid, and triglycerides. This problem of interference is being addressed by the manufacturer.