Dendritic morphology and spine density is not altered in motor cortex and dentate granular cells in mice lacking the ganglioside biosynthetic gene B4galnt1 – a quantitative Golgi Cox study

Scientific paper - Original scientific paper

• Title (croatian): Morfologija dendrita i gustoća spina nije promijenjena u miševa s isključenim B4galnt1 genom za biosintezu gangliozida: kvantitativna Golgi-Cox studija
• Author: Branko Dobrović
• Author: Goran Ćurić
• Author: Zdravko Petanjek
• Author: Marija Heffer
• Author's institution: University of Zagreb; School of Medicine
• Scientific / art field, discipline and subdiscipline: BIOMEDICINE AND HEALTHCARE; Basic Medical Sciences

Abstract (english)

Gangliosides are characteristic plasma membrane constituents of vertebrate brain used as milestones of neuronal development. As neuronal morphology is a good indicator of neuronal differentiation, we analyzed how lack of the ganglioside biosynthetic gene Galgt1 whose product is critical for production of four major adult mammalian brain complex gangliosides (GM1, GD1a, GD1b and GT1b) affects neuronal maturation in vivo. To define maturation of cortical neurons in mice lacking B4galnt1 we performed a morphological analysis of Golgi-Cox impregnated pyramidal neurons in primary motor cortex and granular cells of dentate gyrus in 3, 21 and 150 days old B4galnt1-null and wild type mice. Quantitative analysis of basal dendritic tree on layer III pyramidal neurons in the motor cortex showed very immature dendritic picture in both mice at postnatal day 3. At postnatal day 21 both mice reached adult values in dendritic length, complexity and spine density. No quantitative differences were found between B4galnt1-null and wild type mice in pyramidal cells of motor cortex or granular cells of dentate gyrus at any examined age. In addition, the general structural and neuronal organization of all brain structures, qualitatively observed on Nissl and Golgi-Cox, were similar. Our results demonstrate that neurons can develop normal dendritic complexity and length without presence of complex gangliosides in vivo. Therefore, behavioral differences observed in B4galnt1-null mice may be attributed to functional rather than morphological level of dendrites and spines of cortical pyramidal neurons.

Abstract (croatian)

Gangliozidi su karakteristične sastavnice stanične membrane stanica mozga kralješnjaka koje se rabe kao pokazatelji razvoja neurona. Kako je neuronska morfologija dobar pokazatelj diferencijacije neurona, mi smo analizirali kako nedostatak gena B4galnt1 za biosintezu gangliozida čiji je produkt od kritične važnosti za produkciju četiri glavna kompleksna gangliozida odraslog mozga sisavaca (GM1, GD1a, GD1b i GT1b) utječe na sazrijevanje neurona in vivo. Kako bi utvrdili zrelost kortikalnih neurona miševa s inaktiviranim B4galnt1 genom proveli smo morfološku analizu Golgi-Cox impregniranih piramidnih neurona primarne motoričke kore i granularnih stanica girusa dentatusa u miševa s isključenim B4galnt1 genom i u miševa divljeg soja, starih 3, 21 i 150 dana. Kvantitativna analiza bazalnog dendritičkog stabla sloja IIIc piramidnih neurona motoričke kore pokazala je vrlo nezrelu sliku dendrita u obje skupine miševa starih 3 dana. Miševi stari 21 dana su obje skupine postigli vrijednosti dužine dendrita, složenosti i gustoće trnova (spina) poput one u odraslih životinja. U niti jednoj dobnoj skupini nisu nađene kvantitativne razlike između B4galnt1-null miševa i miševa divljeg tipa među piramidnim neuronima motoričke kore, niti među granularnim stanicama girusa dentatusa bilo koje promatrane dobi. Osim toga, opća strukturna i neuronska organizacija svih moždanih regija, promatrana kvalitativno (Nissl i Golgi-Cox impregnacija neurona), također je bila slična. Naši rezultati pokazuju da neuroni mogu razviti normalnu dendritičku složenost i duljinu i bez prisustva složenih gangliozida in vivo. Radi toga, razlike u ponašanju primijećene kod miševa s isključenim B4galnt1-null genom prije bi se mogle pripisati funkcijskoj, a ne morfološkoj razlici na razini dendrita i spina kortikalnih piramidnih neurona.

• Keywords (english): Animals; Dendrites / enzymology; Dendrites / ultrastructure; Dentate Gyrus / cytology; Dentate Gyrus / enzymology; Gangliosides / metabolism; Hippocampus / chemistry; Hippocampus / metabolism; Mice; Mice, Knockout; Motor Cortex / cytology; Motor Cortex / enzymology; N-Acetylgalactosaminyltransferases / genetics; N-Acetylgalactosaminyltransferases / metabolism; Neurons / enzymology; Neurons / ultrastructure
• Language: english
• Publication type: Scientific paper - Original scientific paper
• Publication status: Published
• Peer review: Peer review
• Publication version: Published version
• Journal title: Collegium Antropologicum
• Numbering: vol. 35, no. S. 1, pp. 25-30
• p-ISSN: 0350-6134
• URN:NBN: urn:nbn:hr:105:771074
• Publication: 2011-01
• Document URL: https://hrcak.srce.hr/64034
• Type of resource: Text
• Access conditions: Open access
• Created on: 2024-03-28 12:01:06