Branchial heart

Ventral view of the viscera of Chtenopteryx sicula, showing the presence of the branchial hearts.

Branchial hearts are myogenic accessory pumps found in coleoid cephalopods that supplement the action of the main, systemic heart.^[1] Each consists of a single chamber and they are always paired, being located at the base of the gills.^[1]^[2] They pump blood through the gills via the afferent branchial veins. Since they only circulate venous blood, branchial hearts function under predominantly anaerobic conditions.^[1] Branchial hearts also appear to be involved in hemocyanin synthesis.^[3]^[2]

Each branchial heart is directly connected to a branchial heart appendage or pericardial gland.^[4] The action of the branchial hearts is necessary for the production of primary urine in these appendages via pressure filtration.^[5] Branchial hearts may have evolved from the pericardial glands of nautiloids, such as those still found in modern nautiluses.^[6]

References

↑ 1.0 1.1 1.2 Fiedler, A. & R. Schipp (1987). The role of the branchial heart complex in circulation of coleoid cephalopods. Cellular and Molecular Life Sciences 43(5): 544–553. doi:10.1007/BF02143583
↑ 2.0 2.1 Cephalopoda Glossary. Tree of Life web project.
↑ Beuerlein, K., R. Schimmelpfennig, B. Westermann, P. Ruth & R. Schipp (1998). Cytobiological studies on hemocyanin metabolism in the branchial heart complex of the common cuttlefish Sepia officinalis (Cephalopoda, Dibranchiata). Cell and Tissue Research 292(3): 587–595. doi:10.1007/s004410051088
↑ Witmer, A. & A.W. Martin (1973). The fine structure of the branchial heart appendage of the cephalopod Octopus dofleini martini. Cell and Tissue Research 136(4): 545–568. doi:10.1007/BF00307370
↑ Schipp, R., H.R. Schmidt & A. Fiedler (1986). Comparative cytochemical and pharmacological studies on the cholinergic innervation of the branchial heart of the cephalopod Sepia officinalis (L.). Cellular and Molecular Life Sciences 42(1): 23–30. doi:10.1007/BF01975878
↑ Bourne, G.B., J.R. Redmond & K. Johansen (1977). Nautilus pompilius: branchial circulation enhanced by an auxiliary pumping mechanism. Cellular and Molecular Life Sciences 33(11): 1453. doi:10.1007/BF01918802

Cephalopod anatomy

Shell

Shell types	External shells: Ammonoid shell Argonautid eggcase Nautiloid shell Orthocone Internal shells: Belemnoid guard Cirrate shell Cuttlebone Gladius (pen) Spirula shell Stylet

External features	Aperture Apex Callus Lirae Periostracum Sculpture Spire Sutures Umbilicus

Internal features	Body chamber Camerae Nacre Phragmocone Septa Siphuncle Whorls

Mantle

External anatomy	Funnel Dermal structures Fins (wings) Mantle locking-apparatus

Internal anatomy	Branchial hearts Ctenidia (gills) Hepatopancreas (digestive gland) Ink sac and ink Needham's sac Nephridia ("kidneys") Nidamental glands Osphradium Pericardial glands

Head and limbs

Brachial crown	Arms Hectocotylus Tentacles

Buccal region	Aptychus Beak Odontophore Radula Spadix and antispadix

Other parts	Eyes Statocysts

General

Chromatophores
Photophores
Nervous system
- Squid giant axon
- Squid giant synapse

Developmental stages: Spawn → Paralarva (Doratopsis stage) → Juvenile → Subadult → Adult • Protoconch (embryonic shell)

This article is issued from Wikipedia - version of the Monday, May 27, 2013. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.