- Collection:
- Atlanta University and Clark Atlanta University Theses and Dissertations
- Title:
- Some in vitro effects of parathormone on the notochord of rana cates-beiana larvae: an electron microscopic study, 1968
- Creator:
- Hogan, James C.
- Date of Original:
- 1968-06-01
- Subject:
- Degrees, Academic
Dissertations, Academic - Location:
- United States, Georgia, Fulton County, Atlanta, 33.749, -84.38798
- Medium:
- theses
- Type:
- Text
- Format:
- application/pdf
- Description:
- The response of cultured amphibian notochord cells to parathor�mone and the structural variations produced has been examined by means of electron microscopy. The investigation was conducted to determine if parathormone would elicit the formation of cartilage in isolated notochordal cells. Excised larval tails of Rana catesbeiana were incubated in 1% versene solution at 37. 5 C for 1 1/2-2 hr and noto�chords were freed by applying external pressure with a blunt instrument. The isolated notochords were cultured in Holtfreter-dextrose solution and varying concentrations of parathormone at temperatures between 3 25-37. 5 C for 24-96 hr. Sections of notochord 1-3 mm were fixed in osmium tetroxide or Luffs fixative and subsequently prepared for electron microscopy. Examination of stained and unstained grid speci�mens revealed increased activity in the peripheral cells, increase in size and abundance of mitochondria and cytoplasmic vesicles. The most prominent features observed in these active peripheral cells were elaborations of many electron dense bodies and clumps of cyto�plasmic contents as a result of rupture of the plasma membranes. The electron dense bodies were found adjacent to the peripheral cell mem�brane, initially, and were observed to be complexes of calcium. These complexes and the elaborated cytoplasmic contents were torn away from the cell as other contents were being expelled. This secreted material was found entering the vacuolated cell area. The increased cellular activity and variation in structure tended to be related to the response of notochordal cells to parathormone.
- External Identifiers:
- Metadata URL:
- http://hdl.handle.net/20.500.12322/cau.td:1968_hoganjr_james_c.pdf
- Rights Holder:
- Clark Atlanta University
- Holding Institution:
- Atlanta University Center Robert W. Woodruff Library
- Rights:
-
