The Comparative Studies On The Tectums Of Gekko Gecko And Eumeces Chinensis And The Fibers Connection Between Nucleus Lentiformis Mesencephali And Tectum In Gekko Gecko

Gekko gecko and Eumeces chinensis (Gray) have different life behavior, the former is nocturnal reptile and the latter is diurnal reptile. Their behave highly depend on the vision which include the tectofugal pathway, the thalamofugal pathway and the accessory optic system. Tectum and nucleus lentiformis mesencephali (LM) is the important part of the tectofugal pathway and the accessory optic system respectively. So the thesis investigates the tectum of Gekko gecko and Eumeces chinensis (Gray), and the fibers connection between LM and tectum in Gekko gecko.Two works have been done in this thesis: (1) Using the HRP labeling methods, measure and note the areas and forms of the neurons in tectum, to compare the similarities and differences of the tectum between Gekko gecko and Eumeces chinensis. The results show that the tectum of the two animals can be subdivided into S zone, C zone and P zone. S zone receives the afferent from retina, and then transfers the information to C zone and P zone. In S zone, the number of tuber of neurons in Gekko gecko is less than in Eumeces chinensis (Gray). The area of neurons of C zone in Gekko gecko is smaller than in Eumeces chinensis (Gray). In Gekko gecko, the percent of small and middle neurons in C zone are higher; In Eumeces chinensis (Gray), the percent of small neurons in C zone and P zone are higher. The differences above indicate that nocturnal Gekko gecko's tectum receiving and dealing with the visual information is less and simpler than diurnal Eumeces chinensis (Gray)'s. So we conjecture that the function of Eumeces chinensis (Gray)'s tectum is more complex. (2) Using the Nissl-stained and HRP labeling methods, to study the structure of LM and the fibers connection between LM and tectum in lizard Gekko gecko. The result of Nissl-stained shows that LM can be subdivided into a dorsomedial and a ventrolateral part. The neurons of the former is far denser than the latter, their neurons are in the similar sizes. Following HRP injections into the anterior tectum, afferents from medial and lateral of tectum arborize respectively in the dorsomedial and ventrolateral of ipsilateral LM, where the bushy nerve cluster and dense terminals are labeled. There are some large labeled neurons in the ventrolateral and the vicinity of LM. We conjecture that those large labeled neurons may have the same function. LM may play an important part in the contact between the tectofugal pathway and the accessory optic system.In the end, some conclusions about the thesis were given.