John Oaks

Department of Comparative Biosciences
Office: 4361

John Oaks

Titles and Education

  1. AB 1964, Colby College
  2. MS 1968, Tulane University
  3. PhD 1970, Tulane University


Primary areas:

  • Parasite regulation of host small intestinal physiology
  • Mechanisms of the tapeworm's integumental function.

Dr. Oaks' research centers upon both sides of the host-parasite interface. Regarding the parasite's side of this interface, his research investigates the protective, communicative and nutritive functions of the tapeworm's surface integument. Tapeworms not only survive in the digestive environment, but also appear to change their surroundings by changing some functions of the intestine. Other research in Dr. Oaks' laboratory focuses on these changed functions, i.e., how the tapeworm controls aspects of the host's physiology. Data collected to date indicate that tapeworms secrete a signal molecule, cyclic guanosine monophosphate (cGMP). When cGMP is released to the lumen, it reduces the motility of the intestine. Slowing of intestinal motility increases the time required for the passage of substances through the lumen of the small intestine, the primary region for absorption of nutritional molecules from digesting food, drugs to treat disease, etc. Application of cGMP to feed increases feed utilization by chickens, presumable by increasing the residence time for nutritional substances as they pass through this absorptive region of the alimentary tract.


Professor Emeritus

Recent Publications

  1. Publications related to current research:
  2. Zimmerman, N.P., Bass, P., and J.A. Oaks. 2005. Succinate enhances the cGMP-altered intestinal motility in the rat. J. Parasitology 91 (1):231-233
  3. Kroening, K.D., N. Zimmerman, P. Bass and J.A.Oaks. 2003. Guanosine 3',5'-cyclic monophosphate: a tapeworm-secreted signal molecule communicating with the rat host's small intestine. J. Parasitology 89:1136-1141 Abstract
  4. Wagner, C., M.K. Clayton, J. Gallegos, P. Bass and J.A. OAKS. 2003. Intraduodenal serotonin elicits non-propagating spike potentials in the small intestine of the rat. Comp Biochem Physiol A Mol Integr Physiol. Nov;136(3):591-603. Abstract
  5. Dwinell, K. L., P. Bass, F. Zou and J. A. Oaks. 2002. Small intestinal transection decreases the frequency of tapeworm-altered myoelectric patterns in the rat. Neurogastroenterology & Motility 14:349-356 Abstract
  6. Kroening, K. D., N. Zimmerman, P. Bass, and J.A. Oaks. 2002. Partial characerization of a tapeworm-secreted signal factor inducing sustained spike potentials in the smooth muscle of the rat small intestine. J Parasitology 88 (2): 227-231 Full text
  7. Dwinell, K. L., P. Bass and J. A. Oaks. 2001. Intestinal regrowth is amplified after jejunal but not ileal resection during tapeworm infection in the rat. Dig. Dis. Sci. 46(9): 1980-4. Abstract
  8. Stark, W.A., J.A.OAKS. 2001. Ileal mucosal mast cell, eosinophil, and goblet cell populations during Hymenolepis diminuta infection of the rat. J. Parasitology 87(5):1222-5.Abstract
  9. Dwinell, K. L., P. Bass, G. L. Telford and J. A. Oaks. 2001. Effect of surgical alteration of the rat gastrointestinal tract on the growth and development of Hymenolepis diminuta. J. Parasitology 87(4):721-4Abstract
  10. Zimmerman, N.P., P. Bass and J. A. Oaks. 2001. Modulation of intestinal permeability in the rat during infection with the tapeworm, Hymenolepis diminuta. J. Parasitology 87(6):1260-3.Abstract
  11. Wise, R. M., P. Bass and J.A. Oaks. 2001. Myoelectric response of the small intestine to the orad presence of the tapeworm Hymenolepis diminuta. J. Parasitology 87(6):1255-9 Abstract
  12. Starke, W. A. and J.A. OAKS. 1999. Mucosal mast cell apoptosis after praziqantel removal of the tapeworm Hymenolepis diminuta from rats. Experimental Parasitology 92:171-181.Abstract
  13. Dwinell, M.B., P. Bass and J.A. OAKS. 1998. In vivo stimulation of rat intestinal myoelectric alterations by Hymenolepis diminuta cellular fractions. J. Parasitology 84: 673-680.Abstract
  14. Dwinell, M.B., R.M. Wise, P. Bass and J.A. OAKS. 1998. Mucosal mastocytosis and smooth muscle hypertrophy in tapeworm infected rats. Experimental Parasitology 89: 92-102. Abstract
  15. Dwinell, M.B., D.M. Schaeffer, P. Bass and J.A. OAKS. 1997. Tapeworm Infection decreases intestinal transit and enteric aerobic bacterial populations. Am. J. Physiology 273: G480-G485.Abstract
  16. Dwinell, M.B., P. Bass and J.A. OAKS. 1995. Praziquantel treatment normalizes intestinal myoelectric alterations associated with Hymenolepis diminuta infected rats. J. Parasitology 81 (6): 979-984. Abstract
  17. OAKS, J. and J. Holy. 1994. Hymenolepis diminuta: Two morphologically distinct tegumental secretory mechanisms are present in the cestode. Experimental Parasitology 79: 292-300. Abstract
  18. Dwinell, M. B., P. Bass and J.A. OAKS. 1994. Intestinal myoelectric alterations in rats chronically infected with the tapeworm Hymenolepis diminuta. Am. J. Physiology 267: G851-G858.Abstract
  19. Holy, J.M., J.A.OAKS, M. Mika-Grieve and R. Grieve. 1991. Development and dynamics of regional specialization within the syncytial epidermis of the rat tapeworm, Hymenolepis diminuta. Parasitology Research 77:161-172.Abstract