ii4 



Effects of Denervation 



flow. So does the acute injection of sympathicolytic agents such 

 as dihydroergotamine, whereas an acute injection of atropine does 

 not affect the flow. 



Some of the observations quoted above are illustrated in Fig. 6.2. 

 In two cats the chorda was sectioned, and 13 days later an acute 

 experiment was carried out. One cat was anaesthetized with mor- 

 phine; a slow paralytic secretion was found from the denervated 



Chloralose 

 Morphine 



Fig. 6.2. Paralytic secretion. 



Secretion from right submaxillary glands of two cats 13 days after chorda section, one under 

 chloralose (uppermost line of records), the other under morphine anaesthesia (second line from 

 above). Time: minutes. Lowest line: signal. In both cats all branches of the right common carotid 

 tied except the artery of the gland. Venous blood from each gland drained off from cannula in the 

 jugular vein after all venous branches except those of the gland had been ligated. Between the two 

 sections of the tracing a crossed circulation was established, blood flowing from central part of 

 right carotid of one cat into peripheral stump of right carotid of the other cat. 2 and 5 are doses 

 of adrenaline, /ig/kg, into the femoral vein of the chloralose cat. At the arrow the adrenals of the 

 morphine cat were removed (Emmelin, 1952). 



gland. The other animal was given chloralose; no secretion was 

 found. A cross-circulation was then established so that arterial 

 blood from the morphine cat perfused the denervated gland of the 

 chloralose cat, and vice versa; after having passed the glands the 

 blood was not allowed to enter the circulation of the recipient 

 animals but was drained off through the cut submaxillary veins. 

 The effect of this procedure was that the paralytic secretion of the 

 morphine cat ceased, and instead a rapid flow started in the chlora- 

 lose cat. Intravenous injection of adrenaline into the chloralose cat 



