The stereological and morfometrical investigation of pars lumbalis of spinal cord in new zealand rabbit

The Stereological and Morfometrical Investigation of Pars Lumbalis of Spinal Cord in New Zealand Rabbit In the study, 12 (6 females, 6 males) adult New Zealand rabbits were used with on the purpose of examining the morphometric and streological values. After the rabbits were euthanized, their biometric data (weight, head-tail length) were recorded and kept in 10% formaldehyde solution for 6 days. Then the segmentation process of the medulla spinalis was performed and the morphometric parameters of each segment were recorded. After that, follow-up process was completed for histological procedures. The method was determined with a preliminary study before the volume calculations were made with the Cavalieri principle in the medulla spinalis. In the preliminary study, tissue sections of 5 μm thickness were taken from each lumbal segment. Sampling rate was determined as 1/200 and an average of 10-16 sections were obtained from each segment. The sections obtained were stained with Hematoxylin Eosin and Luxol Fast Blue. After stained sections were photographed, then substantia alba, substantia grisea and total segment volume were calculated according to the Cavalieri principle by transferring image J programme. As a result, it was observed that 38% of the length of the medulla spinalis in female and male rabbits belonged to the pars lumbalis. It was determined that morphometric parameters were not statistically diffirent between male and female rabbits (P> 0.05). It was determined that the segment with the biggest volume value in the pars lumbalis was L5. In female and male rabbits, this value was 150.30 mm3 and 161.24 mm3, respectively. Substantia alba's biggest volume value belonged to the L4 segment. This value in female and male rabbits is determined as 109.34 ± 30.18 mm3 and 117.90 ± 27.70 mm3, respectively. It was observed that the volume value of substantia grisea was the biggest in the L6 segment in both genders. This value was recorded as 54.46 ± 8.14 mm3 and 54.25 ± 13.42 mm3 in female and male rabbits, respectively. When the average volume values of lumbal segments were compared according to gender, it was determined that there was no statistically significant diffirence (P> 0.05). However, this value was observed to be bigger in male rabbits. In both genders, when the correlation values of the volume values (total lumbal volume, substantia grisea and substantia alba volumes) were compared with the weight and head-tail length of the rabbit, it was observed that this value was not statistically significant (P> 0.05). As a result, this study is thought to be a reference to the researchers to review the neuroanatomy of the lumbal part of the medulla spinalis in New Zealand rabbits and to localize the neurological studies to be conducted in this type.