STUDY OF THE VESICAL PRESSURE PART 1 EXPERIMENTAL STUDY OF THE VESICAL PRESSURE

2. THE VESICAL PRESSURE AFTER REMOVING THE ABDOMINAL PRESSURE

Abstract

In the chapter one, the author dealt with the relations between the vesical and abdominal pressures, which have been based on scant experiments. The author pointed out that the two pressures, under normal conditions, keep always parallel inter-relations each other, and classified, on the other hand, various pharmacologic agents into five groups, according to their effects upon the bladder in considerations of the abdominal pressure. While in the present chapter, the author undertakes experiments to reveal the vesical pressure alone, trying to get rid of the abdominal pressure, and ascertains the conclusions of the previous chapter.
Method of Study.
The instillment apparatus and other particulars are likewise as in the chapter one. However, a metal tube, specially prepared, is introduced through the abdominal wall in its lower part after incision in order to eliminate unnecessary factors by the abdominal pressure. By stiching the incised wall upon the metal tube, this purpose is attained; still the general conditions stay almost normal without injuring the innervations of the bladder. Namely, the abdominal pressure no longer influences the vesical pressure, the fenestrated abdominal wall keeping the internal organs including the bladder from cold and drying.
Results.
1 After the abdominal pressure is removed, the so-called “great curve” of Yoshida no longer appears. Accordingly the great curve in the bladder of living rabbits appears as an effect of the abdominal pressure.
2 The reflex capacity of the bladder is attained at less capacity. The abdominal pressure, therefore, makes more urine accumulate in the bladder.
3 Micturition reflex as well as urination are still functioned.
4 Pharmacological effects:
1) Pilocarpin raises the vesical pressure without reference to the abdominal pressure.
2) Atropin, not less than 0.5mg. per kg. body weight, lowers the vesical pressure, less dose causing no change. This shows the descent of the vesical pressure in living rabbits, when the dose not more than 0.1mg. per kg. body weight is applied, is secondary, being caused by the descent of the abdominal pressure. To bring descent of the vesical pressure by the vesical relaxation, more than 0.5mg. per kg, body weight should be applied.
3) Adrenalin lowers the pressure without reference to the abdominal pressure, after temporary ascent, which dose not present after pituitrin is injected. Adrenalin lowers the pressure stronger than atropin.
4) Cholin raises the vesical pressure without relation to the abdominal pressure.
5) Pituitrin raises the vesical pressure, but no rythmic movements can be seen, so remarkable, great and regular as seen in the normal animals. This shows that the rythmic movements are caused by those of the abdominal pressure.
6) Strychinin raises the pressure, first when a dose is applied enough to cause cramp. So the ascent of the normal animals, when no cramp happens, is merely an appearance caused by the abdominal pressure.
7) BaCl₂ causes the ascent of the pressure and striking rythmic movements. We need not consider, therefore, the abdominal pressure in this connection.
8) Vagostigmin raises the pressure and intensifies the rythmic movements after an interval of several to twenty minutes after application. Here, the abdominal pressure does nothing to the bladder.
9) Urotropin raises the pressure by filling the bladder with urine. The abdominal pressure does not refer to it, but the phenomenon is more rapid than in normal rabbits.