Effect on breathing of ventral medullary surface cooling in neonatal goats. J Appl Physiol (1985) 1996 Jun;80(6):1949-57
Date
06/01/1996Pubmed ID
8806899DOI
10.1152/jappl.1996.80.6.1949Scopus ID
2-s2.0-0030015519 (requires institutional sign-in at Scopus site) 8 CitationsAbstract
The present study was designed to determine whether neurons near the ventral medullary surface (VMS) that are important to control of breathing in adult mammals are also important to control of breathing in neonates. In 7-day-old goats (n = 22), the VMS was surgically exposed under halothane anesthesia. Stainless steel thermodes (2 x 2 mm) were used to cool (20 degrees C) and thereby create neuronal dysfunction of discrete VMS sites. Bilateral cooling under anesthesia 0-2 or 2-4 mm lateral to the midline between the exit of cranial nerves VI and XII resulted in a reduction (P < 0.05) of breathing and most often in apnea. Cooling caudal or rostral to this area did not have a consistent effect on breathing. In 7-day-old goats (n = 8), 3 x 3-mm thermodes were chronically implanted bilaterally on the VMS surface between the exit of cranial nerves VI and XII. The goats recovered and were studied over several days thereafter. VMS cooling while the goats were awake caused breathing to decrease (P < 0.05), but apnea was never observed. The decrease was less (P < 0.05) than while the goats were anesthetized. After 10 s of cooling, the hypopnea while the goats were awake was uniform during eupnea, hypercapnia, hyperoxia, and hypoxia, but after 10 s of cooling, the decrease was relatively greater (P < 0.05) during hyperoxia and hypercapnia. These effects of VMS cooling are qualitatively the same as in adult goats; thus the data are consistent with mature VMS contribution to the control of breathing in neonatal goats.
Author List
Lowry TF, Forster HV, Pan LG, Ohtake PJ, Epshteyn I, Korducki MJ, Franciosi RAAuthor
Hubert V. Forster PhD Professor in the Physiology department at Medical College of WisconsinMESH terms used to index this publication - Major topics in bold
AnimalsAnimals, Newborn
Female
Male
Medulla Oblongata
Respiration
Sheep
Temperature