36 KB1480 KB22 KB200020242001Cedilnik, AntonKocmur, LauraKošmelj, KatarinaRupnik, MarjanVeranič, PeterZorec, RobertZupančič, Gregorštevilka:2letnik:207 stranistr. 79-85COBISSID:10862681ISSN:1580-3139URN:URN:NBN:SI:doc-2JWA6AD1enDruštvo za stereologijo in kvantitativno analizo slike, Medicinska fakultetaImage analysis and stereologyceliceintergranularna fuzijapodganestereologijaIntergranule fusion in rat pars intermedia cells|Using electron microscopy, we studied the morphology of secretory granules in rat pars intermedia cells. We found figures of apparent intergranule fusion, characterized by a tight association of two granules. The fusion was detected in around 2% of all measured granules, indicating a low occurence of intergranule fusion. To study whether intergranule fusion affects the distribution of granule diameters a simple probabilistic model was developed. It is based on the theory that larger granules are formed by fusion of two or more spherical granules of fixed size, and that the surface of a newly formed granule is equal to the sum of fused granule membranes. The model accounts for the bias on granule diameter measurements due to sectioning of granules. Although the electrom microscopy data strongly indicates the existence of intergranule fusion in rat melanotrophs, this process as modelled in present work does not contribute to the granule diameter distribution significantly. It is likely that in addition to the fusion of larger granules, other processes, such a fusion of microvesicles, may affect the distribution of granule diametersZ elektronskim mikroskopom smo študirali morfologijo sekundarnih granul v podganjih "pars intermedia" celicah. Pri okoli 2% merjenih granulah smo opravili tesno asociacijo para granul, ki sugerira zlivanje granul. Za študij takega zlivanja smo uvedli preprost verjetnostni model, po katerem večje granule nastajajo z zlivanjem nekih osnivnih enot, pri čemer se površine preprosto seštevajo. Model upošteva razliko med premeri sekcij granul in njihovimi dejanskimi premeri. Čeprav osnovne slike prepričljivo sugerirajo pravilnost teze, pa model teze ne potrdi signifikantno. Domnevamo, da tudi drugi procesi, kot naprimer fuzija mikroveziklov, vpliva na porazdelitev premerov granulTEXTznanstveno časopisjejournalsSlovenian National E-content AggregatorNational and University Library of SloveniaDruštvo za stereologijo in kvantitativno analizo slike