The comparative investigation of left ventricle papillary muscle arteries in different species.

OBJECTIVE: To determine whether similar histologic findings exist in left ventricle papillary muscle arteries in different species and to elicit whether those animal hearts may be used as models for human heart in experimental studies related to papillary muscles. METHODS: We examined 360 samples taken from the tip, mid-portion and base of papillary muscles in 60 normal adult hearts (15 each from human, dog, sheep, goat). The samples were obtained from Dicle University and Kahramanmaras Sutcu Imam University, Turkey and the study was conducted in June-September 2004. Tissues were processed by routine histologic methods, stained with hematoxylin-eosin and van giesson, and later evaluated under a light microscope. RESULTS: While the values of human and dog heart resembled each other by means of left ventricle papillary muscle arteries, the hearts of sheep and goat were also found to be similar. The number of thin walled arteries increased from the tip (18%) to the base (48%), intermediate walled arteries decreased from the tip (56%) to the base (14%), thick walled arteries decreased from the tip (62%) to the mid-portion (38%). The differences among human and animals were not statistically significant in any group. We found that the thickness values of papillary muscle arterial walls at the tip, mid-portion and base varied from 4.86 microm to 107.7 microm in all species. The difference among values of human and animals was not significant statistically (p>0.05). CONCLUSION: The values for arterial walls of tip, mid-portion and base of papillary muscles were similar between human and dog, sheep and goat. These morphologic findings in human and animal hearts of different species prove that anatomists, cardiologists, experimental investigators, pathologists and physiologists may benefit from the hearts of those animals as a good model to imitate the human heart in experiments concerning papillary muscles.

Morphology of the lumbar spinal canal in normal adult Turks.

Pathological changes can occur in the diameters of the lumbar spinal canal. Therefore, assessing the canal size an important diagnostic procedure. Two hundred plain anterioposterior radiographs of the lumbar spine were examined. The sample consisted of 100 males and 100 females. The transverse diameter of the bony spinal canal (interpedicular distance), which was measured as the minimum distance between the medial surfaces of the pedicles of a given vertebra, was measured. In addition, the transverse diameter of the vertebral body, which was measured as the minimum distance across the waist of the vertebra, was measured. The distances were measured to the nearest one tenth of a millimetere using a Vernier caliper. At all levels (L1 - L5) the transverse diameters of the lumbar spinal canal were approximately 1 - 1.5 mm higher in males than in females. The intersegmental differences increased proximodistally, in both sexes. The ratio of the transverse diameter canal to the width of the vertebra ranged from 0.55 to 0.60 mm in both sexes. The distribution of the different lumbar canal types were 47% A, 42% B, 11% C. Additionally, subtypes were determined and classified.