Olivocerebellar projection

O Hearn E, Molliver ME. (1997). The olivocerebellar projection mediates ibogaine-induced degeneration of Purkinje cells a model of indirect, transsynaptic excitotoxicity. J Neurosci. 17(22) 8828-41. 

Yip J, Marcon R, Kemper TL, Bauman ML, Blatt GJ (2005) The olivocerebellar projection in autism using the intermediate filament protein peiipheiin as a marker for climbing fibres. Int Meet Autism Res Abs (IMFAR) 5 49. 

This is one of the reasons for the longitudinal, strip-like organization of the olivocerebellar projection (see Section 6.3.3.). Transverse branching is limited to climbing fibers terminating in certain longitudinal strips (Ekerot and Larson, 1982). 

Only few observations in primates are available on the corticonuclear projection of the posterior lobe. Haines and Whitworth (1978) and Haines and Patrick (1981) studied the projection of the paramedian lobule and the paraflocculus in the tree shrew Tupaia glis). They concluded that , 3 and a D zone, with a similar topography and corticonuclear projection as in the cat, were present in the paramedian lobule of the tree shrew. The C2 and the D zone continued into the paraflocculus, where the D zone could be subdivided into D, and Dj zones on the basis of its differential projection to the lateral cerebellar nucleus. The organization of the posterior vermis in primates (Haines, 1975a,b) will be dealt with in the Sections on the vestibular cerebellum (6.1.5.) and the olivocerebellar projection (6.3.3.3.). 

Fig. 150. Diagram of the afferent olivocerebellar projection according to Katayama and Nisimaru (1988) and the efferent projection of the zones of the nodulus to the vestibular and cerebellar nuclei according to Wylie et al. (1994) in the rabbit. P = group 8 of the medial accessory olive DC = dorsal cap of Kooy F = fastigial nucleus IP = posterior interposed nucleus MV = medial vestibular nucleus P cell = Purkinje cell SV = superior vestibular nucleus VLO = ventrolateral outgrowth I-VI = zones of rabbit nodulus, numbered according to Katayama and Nisimaru (1988).

The olivocerebellar projection has been studied mainly in the cat (see Brodal and Kawamura, 1980 and Voogd, 1982 for reviews). Fewer data are available for primates and sub-primates (Brodal and Brodal, 1981, 1982 Whitworth et al., 1983 Whitworth and Haines, 1986b). A more complete picture of the olivocerebellar projection in the rat is emerging (Buisseret-Delmas and Angaut, 1993 Ruigrok and Celia, 1995 Voogd,... 

When the olivocerebellar projection was studied in the cat with antegrade axonal transport of tritiated aminoacids it appeared that the labelled climbing fibers were arranged... 

Fig. 172. Origin from the border region of the rostral and caudal medial accessory olive of the olivocerebellar projection to the electrophysiologically identified x zone in the cat, a = a zone b = b zone P = subnucleus beta cpCj = CpC, zones coll = inferior colliculus d, dj = d, and d2 zones dmcc = dorsomedial cell column MAO = medial accessory olive ml = midline pvg = lateral border of vermis x = x zone IV, V = lobules IV and V. Redrawn from Campbell and Armstrong (1985).

The organization of the olivocerebellar projection to the anterior vermis in primates appears to be similar to the cat (Brodal and Brodal, 1981 Whitworth and Haines, 1986b) (Fig. 178). Olivocerebellar projections to the A, X and B zones were identified in a preliminary report on Macaca fascicularis by Voogd et al. (1987a,b, 1990). The projection to the A zone resembles the situation in the cat with respect to the presence of A[ and A2 subzones. Olivocerebellar projections to the X zone take their origin from intermediate levels of the MAO, that also project to the C2 zone. A collateral projection to Deiters nucleus detaches from olivocerebellar fibers to the B zone. Projections from the DAO and the dorsal and ventral leaf to the hemisphere of the anterior lobe were described by Brodal and Brodal (1981) in macaque monkeys and C, C2 and C3 and D zones were identified by Whitworth and Haines (1986) in the olivocerebellar projection to the anterior lobe in Saimiri sciureus. 

It receives a projection from the subnuclei a, b and c of the caudal MAO. The origin of this projection in the rat appears to be more extensive than in the case of the X zone of the cat (compare Fig. 172) (Campbell and Armstrong, 1985). They also identified a CX zone in the lobules V and VI, medial to the Cj, on the basis of its projection to the interstitial cell groups. It received its olivocerebellar projection from the group c at middle and rostral levels of the MAO. 

Buisseret-Delmas and Angaut (1989b, 1993) defined three D-zones in the lateral part of the anterior lobe on the basis of their corticonuclear projection to the dorsolateral hump (Do), the dorsal magnocellular part of the lateral cerebellar nucleus (D,) and the ventral parvicellular part of this nucleus (Dj). They receive their olivocerebellar projections, respectively, from the DM group and the medial half of the ventral leaf of the PO (Do), the dorsal leaf of the PO (D,) and the lateral half of the ventral leaf of the PO (D2) (see Fig. 141). 

Several aspects of the olivocerebellar projection have been studied mainly in the rat. 

The zonal distribution of the olivocerebellar projection was first demonstrated by Chan-Palay et al. (1977), using autoradiography of antegrade axonal transport of S-methion-... 

The zonal disposition of Zebrin-immunoreactive and non-immunoreactive Purkinje cells has not been compared in any detail to the olivocerebellar projection. According to Gravel et al. (1987) some of the borders between Zebrin-positive and negative zones coincide with borders of certain climbing fiber strips, but these strips were not further identified. Judging from the reported identity of some of the Zebrin-positive and -negative zones with certain corticonuclear and cortico-vestibular projection zones it seems likely, that the correspondence between the zonal organization in the olivocerebellar projection and the Zebrin pattern will be close (Fig. 181). 

Jeneskog (1974) recorded climbing fiber evoked potentials in the Cj and d zones of the anterior lobe and the paramedian lobule, after stimulation in and around the red nucleus. Rubral and spino-olivary pathways converge upon these zones the DLF-SOCP terminates in the d zone, and the hindlimb and forelimb components of the DF-SOCP in the ventral and dorsal portions of the c, zone of the paramedian lobule (Jeneskog, 1981a). Tentatively they identified a C3 zone in the dorsolateral paramedian lobule and located the Cj zone in the central region of this lobule after mesencephalic stimulation. The total picture of the olivocerebellar projection to the paramedian lobule is less complete, but still very similar to the anterior lobe, with fusion of the C, and C3 zones in its ventralmost part. The discontinuity of the C3 zone in the dorsolateral and ventrolateral parts of the lobule allows the Cj zone to leave the paramedian lobule to enter the paraflocculus. 

Fig. 185. The olivocerebellar projection to the pyramis and the uvula (lobules 8 and 9) of tbe rat cerebellum. A,B- Olivocerebellar projection zones of the lobules 8 and 9. C. Origin of these projections, indicated in diagrams of transverse sections through the inferior olive, a = subnucleus a of the medial accessory olive b = subnucleus b of the medial accessory olive beta = group beta c = subnucleus c of the medial accessory olive d = dorsal accessory olive dm = dorsomedial subnucleus m = medial accessory olive pr = principal olive 8 and 0 = lobules VIII and IX of Larsell. Relabelled and reproduced from Eisenman (1984).

There is a good correspondence between the organization of the olivocerebellar projection in the rat and the cat. The main exceptions are the presence of the lateral extension of the A zone (or tectal response zone) and the Dq zone in the hemisphere of... 

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