THE PANCREATIC JUICE, 



303 



unstnatcd muscular fibers mainly pursuing a circular course, and lined internally 

 by a single layer of cylindrical epithelium. Small mucous glands lie in the main 

 duct and in its larger branches. Medullated and non-medullated nerves which 

 in their course are connected with ganglia, pass to the glandular acini' but their 

 terminations are unknown. Blood-vessels surround the acini, in part of large 

 size and in abundance in part isolated. The fresh pancreas contains water , 

 albummates ferments, fats and salts. The resting gland contains much leucin 

 isoleucm and tyrosm; further, butalanin, often xanthin and guanhv lactic acid' 

 formic acid, fatty acids; most of these from autodecomposition. 



THE PANCREATIC JUICE. 



To obtain the pancreatic juice Regner de Graaf, in 1664, tied in the excretory 

 duct of a dog a cannula provided with an empty bag at its extremity, in which 

 the juice collected Others passed the tube through the abdominal walls exter- 

 nally and thus made a transitory cannula-fistula, which closed in the course of a 

 tew days, with inflammatory expulsion of the extremity of the cannula that had 

 been tied m place. In order to establish a permanent fistula, either a duodenal 

 istula is made, like a gastric fistula, through which the duct of Wirsung is cathe- 

 tenzed by means of a thin tube ; or the duct is opened in a dog and drawn toward 

 the abdominal wound and an attempt is made to unite the wound in the duct 

 with the abdominal wound so as to form a fistula. Heidenhain eliminates the 

 portion of the duodenum in which the duct opens from the continuity of the 

 intestine, incises it, and fixes it outside of the abdominal wound. 



From such a permanent fistula an abundant, feebly active, watery 

 secretion, rich in sodium carbonate, is collected. From a freshly made 

 opening and before the onset of inflammatory processes, a scanty viscid 

 fluid is obtained which exerts energetic and characteristic physiological 

 actions. 



Obviously, the scanty, viscid secretion is normal, while the watery, 

 abundant secretion is abnormal and derived from the dilated blood-ves- 

 sels, perhaps in consequence of paralysis of the vasomotor nerves, and 

 as a result of increased transudation. The latter would thus in a cer- 

 tain sense be a paralytic secretion. The amount must vary greatly, 

 accordingly as viscid or watery secretion is produced. During digestion 

 a large dog secreted from i to 1.5 grams of viscid secretion; Bidder 

 and Schmidt obtained from a permanent fistula from 35 to 37 grams of 

 watery secretion in twenty-four hours, for each kilogram of weight. 



While the resting, inactive gland is flabby, yellowish red in color, the 

 secreting gland is turgescent and reddened from the dilatation of its 

 blood-vessels. 



Normal pancreatic juice is transparent, colorless and odorless, with a 

 salty taste, and a strongly alkaline reaction from the presence of 0.4 per 

 cent, sodium carbonate, and therefore effervescent from escape of car- 

 bon dioxid on addition of acid. It contains albumin and potassium 

 albuminate (9.2 per cent.); like watery egg-albumin, it is viscid, flows 

 with difficulty and coagulates at a temperature of 75 C. into a white 

 mass. On standing in the cold a gelatinous coagulum of albumin sepa- 

 rates, in which concentrated mineral acids, metallic salts, tannic acid, 

 chlorin-water and bromin-water cause a precipitate; the precipitate 

 produced by alcohol can be redissolved by water. The total solids in 

 the pancreatic juice of human beings equal 13.6 per cent. Among the 

 salts are sodium chlorid, 7.3; sodium bicarbonate, 0.4; sodium phos- 

 phate, 0.45; sodium sulphate, i.i in 1000, together with some lime and 

 traces of magnesia, potassium sulphate and ferric oxid. 



The more rapid and the more profuse the flow of the pancreatic 



