SURVEY OF ENDOCRINE ORGANS  ©David B. Fankhauser, Ph.D., Professor of Biology and Chemistry University of Cincinnati Clermont College, Batavia OH 45103
Pineal Gland  (above  corpora quadrigemina)	File "Endocrine_organs.htm" was last modified on 30 Dec 2004.  This page has been accessed times since 24 February 2003.  3 March 1992, latest revision 22 Feb '96, 4 Jan. '97, 27 Feb '97, 6 Jan 03	ovaries and uterine  horns in the cat

This lab uses a cat which has been opened from stem to stern on the ventral surface as directed in the protocol Nerves to Locate in the Cat. You will need to know italicized features in order to locate the listed endocrine organs in bold. The page references to the illustrations in Gilbert's Pictorial Anatomy of the Cat are given in parentheses. Illustrate a small view of the brain and a large view of the neck and trunk showing all bold and italicized features. At home, list the hormones produced and describe their functions for each endocrine organ named.  Here is the page discussing the histology of endocrine organs .

I. HEAD: If you did not dissect your cat's cranium, find a student who did.

	PITUITARY: Find the sella turcica on the floor of the cranium where the pituitary was once located. Probably part of it remains (p. 39 & 83). The ring shaped structure is its infundibulum.  Lower image:  In this dissection, the pituitary remains attached to the brain just behing the optic chiasma.
	PINEAL GLAND:  The pineal gland can be seen just superior to the corpora quadrigemina on the rear medial surface of the brain. (p. 78) It produces melatonin except when light strikes the retinas.

II. NECK   Here is a labeled view of the endocrine organs of the neck and thorax (and nearby organs for reference).

	THYROID:  Two globular organs inferior to the larynx and adhering lateral to the trachea are the two lobes of the thyroid glands. (p.47) (In the human they are joined by a prominent isthmus.)  Thyroxine is produces in the follicles and calcitonin produced in the parafollicular cells.
	PARATHYROID  Attached to the thyroid on its dorsal side are the parathyroid glands, which are tiny and nearly invisible. Note that they are presumed there, even though not seen.  It produces parathormone.

III.  THORAX

THYMUS:  In the mediastinum, the thymus is ventral to the trachea, superior to the heart. (p. 42)

IV.  ABDOMEN
Reflect the two abdominal wall flaps to expose the abdominal organs.  Here is a labeled view of the undissected abdominal contents.   

	STOMACH:  The stomach lies under the liver to the left.  It secretes gastrin which triggers gastric secretions. DUODENUM:  The duodenum is immediately distal to the stomach, and secretes secretin which triggers pancreatic secretions, and cholecystokinin which among other actions, triggers contraction of the gall bladder. PANCREAS:  The pancreas is nestled along the inside curve of the duodenum (just downstream from the stomach), and appears diffuse and slightly fatty. (p. 43-50) The green stain on the duodenum shows where the bile duct enters the small intestine. The pancreatic duct enters here too. Here is a labeled view of the GI tract endocrine organs.
	KIDNEYS: Gently move the intestines one side so that you can see the kidneys at the rear of the abdominal cavity. Here is a labeled view of the kidney, adrenal gland, and nearby organs of the rear abdomen.
	ADRENALS:  The adrenals are globular organs superior to the kidneys, under the prominent adrenolumbar vein. Both are retroperitoneal. (p. 55) (In humans, they rest on the kidneys, but not in the cat.)
	OVARIES:  If your cat is a female, find the oval-shaped ovaries associated with the fallopian tubes, inferior to the kidneys and attached to the rear of the abdominal wall. (p. 55) Here is a labeled version of the lower abdominal female reproductive organs
	TESTES:  If you have a male cat, the testes can be felt in the scrotum. (p. 56) Find the spermatic cord which runs infront of the pubic bone carying the testicular veins which carry blood-borne testosterone.   towards the heart where enters the abdomen (look for the vas deferens looping over the ureters at the bladder). Inspect a cat of the opposite sex of the one you are using so you see both sets of gonads.  Here is a labeled view of the testis and spermatic cord.

CLOSING UP: When you have finished your dissection, reposition the internal organs in their proper locations, close the abdominal flaps, wrap in the skin, place in the plastic bag, press out the air, seal with 2-3 turns of a rubber band and return to the box, numbers to the right. Wash your desk top with warm slightly soapy water. Wash your instruments well, dry them, replace in storage. Check the sinks and the floor around your desk to be sure they are thoroughly clean.