Pancreozymin in man as in animals appears to act as a specific enzyme stimulant. The preparations of pancreozymin used in these experiments also contain cholecystokinin, which causes the gall bladder to contract, and a smooth muscle stimulant, possibly substance P. The duodenal contents obtained in response to a standard dose of secretin and pancreozymin have been collected quantitatively in man and the volume and amount of bicarbonate, amylase, trypsin, and lipase measured in order to study pancreatic function. The results of 105 tests undertaken on a normal group, in pancreatic and biliary disease, and in non-pancreatic steatorrhoea have been analysed. In localized pancreatic lesions and after recovery from acute pancreatitis, normal function is often retained. Mild functional impairment may be demonstrated only by a poor enzyme output in the post-pancreozymin fractions, while at a later stage bicarbonate output is affected and finally the volume of the duodenal contents is reduced. The secretin-pancreozymin test is most valuable, therefore, in the more chronic and advanced forms of pancreatic disease in which it gives a good assessment of residual pancreatic function. In diagnosis care must be taken in interpreting a functional test in terms of anatomical pathology. The test has proved useful not only in diagnosis but also as a guide to treatment and an index of prognosis.
1. Extracts of antral mucosa increase the output of pancreatic amylase. They do not stimulate the resting pancreas of the anaesthetized cat to secrete juice, but have a slight ‘secretin‐like’ effect on a pancreas already responding to endogenous or exogenous secretin. 2. In animals with the vagus and splanchnic nerves cut instillation of meat extracts or acetylcholine into the antrum stimulates gastric acid and pancreatic amylase secretion. These responses can be prevented by injection of atropine or cocainization of the antral mucosa. 3. In animals with the splanchnic nerves cut but the vagus nerves intact, distension of the body or antrum increases the output of amylase. After vagal section distension of the body has no effect on the pancreas, but the response to antral distension is still present. 4. It is concluded that there is a gastric phase of pancreatic secretion which, in the cat, is almost entirely a stimulation of enzyme output. A vago‐vagal reflex pathway is required for the pancreatic response to mechanical stimulation of the body of the stomach, and may be involved in the response to antral stimulation. Chemical and mechanical stimulation of the antrum produces a hormonally mediated increase in pancreatic enzyme secretion. The effects of atropine and cocaine on this response are consistent with the view that the release of the antral stimulant depends on a local cholinergic reflex pathway in the antrum.
The purpose of this study was to determine if muscle strength influences the hyperemic response to dynamic exercise. Men with low (n=8) and high (n=9) maximal forearm strength performed dynamic handgrip exercise as the same absolute workload increased in a ramp function (0.5 kg x min (-1)). Forearm blood flow (FBF) was measured instantaneously by ultrasound Doppler and blood pressure was measured by auscultation. The pressor response to exercise was greater (P<0.05) for low strength men at workloads >1.5 kg allowing volumetric FBF (ml x min (-1)) and vascular conductance to increase in proportion to absolute workload similar to high strength men. When FBF was expressed relative to forearm volume (ml x min (-1).100 ml (-1)) the hyperemic response to exercise (slope of relative FBF vs. workload) was greater in low strength men (3.2+/-1.5 vs. 1.7+/-0.4 ml x min (-1).100 ml (-1) x kg (-1), P<0.05) as was relative FBF at workloads >1.5 kg. However, when relative FBF was compared across relative work intensity, no difference was found between low and high strength groups. Together, these findings suggest men with low strength require a greater pressor response to match blood flow to exercise intensity as compared to high strength men.
