Vasopressin release in response to intravenously injected contrast media

We have previously reported that intravenously administered contrast media produce a rise in plasma vasopressin (antidiuretic hormone) concentrations. We have now shown that this occurs both when contrast medium is injected into a peripheral vein and when it is centrally injected into the right atrium. The peak vasopressin concentration recorded varies with the osmolality of the contrast medium. The vasopressin response was greater when contrast agent was centrally injected.